Reappraising the Origins of Exclusion in Late Medieval Castile: Across the Boundaries Between Religion, Politics and Customs

Abstract

Over the past two decades, research on issues of agency and liminality around borders has highlighted the mutual permeability, fluidity and overlapping of spheres such as religion and politics, providing arguments on the construction of identity and otherness that allow us to reappraise long-standing historical debates. This framework is particularly illuminating for the case of 15th-century Castile, when consolidation of a pioneering centralized monarchy in Europe witnessed the end of the coexistence between Christian, Jewish and Muslim communities, eventually leading to the persecution of converts and the expulsion of cultural and religious minorities. Drawing upon both primary and secondary sources, and adopting the analytical framework of frontier-crossing, this article identifies the conditions under which particular social agents reconfigured the boundaries between religion and politics in 15th-century Castile. It further examines the process by which border crossing by various agents made customs and everyday practices crystallize into a third sphere for the construction of alterity and exclusion and analyzes the specific context in which the intersection of these three domains contributed to the stigmatization of Jews, Muslims and converts, ultimately leading to their exclusion and expulsion. Initially subordinated to theological and legal concerns, social practices, rituals and ceremonies became central to discourse intersecting the political, religious and moral domains, underpinning social stigmatization and the institutional mechanisms of rising monarchical centralization.

1. Introduction: Incorporating Customs into the Study of the Shifting Boundaries Between the Political and the Religious Spheres

There are two views embedded in Western culture on the relations between religion and politics. One is the image of “communicating vessels”, in which as the sphere of politics grows, that of religion is diminished (Talmon 1952); the other is the tradition of “political theology”, in which the distinction between friend and enemy that founds the political sphere is supplemented with the logic of inclusion/exclusion at the core of the religious sphere (Schmitt [1963] 2007). Despite their differences, in both approaches religion and politics are assumed to feature rather flexible and porous boundaries, allowing for mutual interactions; however, through their cross-border exchanges, groups institute rather essentialist and fixed images about others and themselves. In historical studies, permeation between the religious and political spheres has also been highlighted (i.e., Walzer 1965; Hill 1982; for the English Revolution), with borders as “channels of communication” contingently defining cleavages that separate ethnic or religious groups (Tilly 2006; Stark 1998; Barth 1969; Parker 2006; Parker and Rodseth 2005; Pavlakovish-Kochi et al. 2004).

This article aims to contribute to the long-standing debate on the relationship between religion and politics, and on its related sequels of social inclusion/exclusion, by reappraising a historical case of interactions among three religious communities—Christians, Muslims and Jews—that affected the established political boundaries. These three monotheistic confessional groups coexisted in the Iberian Peninsula through the Middle Ages within both Christian and Islamic political–territorial formations (García Sanjuan 2015, pp. 93–110; Mann et al. [1992] 2007; Scarborough 2014, pp. 1–14); yet, as is well known, the 15th century assisted the breakdown of cohabitation, ending in the expulsion of Jews from the Crown of Castile in 1492—as the last Muslim stronghold of Granada was conquered—and the establishment of the Inquisition for social control and the repression of those newly converted to Christianity (Kamen [1965] 2023).

The aim of this article is to reappraise the origins of the expulsion of Jews and the exclusion of converts by approaching the issue from the perspective of border crossing. Irrespective of their degree of entanglement, studying the crossing between the spheres of politics and religion requires identifying some kind of agency interacting at their borders. One basic assumption of our approach is that shifts in the established boundaries between religion and politics were the result of processes enacted by the activities of go-betweens. The other tenet is that to fully understand and account for patterns of social inclusion and exclusion, the study of the relations between politics and religion must incorporate customs or social habits as a distinctive sphere with its own logic and historical profile.

From these premises, there are three research questions to answer regarding border shifts and their influence on social and institutional trends at the origins of the early-modern Hispanic monarchy: Under which conditions and by the intervention of which agents were the established borders between religion and politics altered in the late Middle Ages? How and why did customs and habits become a distinct discursive sphere deployed to define otherness and justify social exclusion? And finally, to which extent did boundary shifts contribute to the stigmatization mechanisms associated with Jews and conversos eventually leading to their expulsion or exclusion?

Following a section reflecting on borders as a methodological approach to the study of political and religious changes in 15th-century Castile, Section 3 offers an overview of the first half of the century presided by expansion of the political sphere while highlighting the activities of go-between actors crossing its borders with the religious sphere; Section 4 analyzes the emergence by the middle of the century of customs as a result of processes affecting the relations between the political and religious spheres, and Section 5 examines the role of the boundary shifts among the three spheres in the stigmatization of Jews and New Christians at the end of the century. The empirical basis of this article draws on secondary literature and a published body of documents comprising theological treatises and polemics, sermons, court and inquisitorial records and royal and municipal charters.

2. Theory and Methodology: The Crossing of Borders, the Shifting Boundaries of the Political and the Historical Definition of Customs

Through the classic metaphor of doors and windows, borders appear as lines of demarcation that separate but at the same time connect what they divide (Simmel 1994). With globalization and the increase in migration across countries, this duality has prompted us to differentiate rather porous borders from more rigid and institutionalized frontiers (Giddens 1987); yet it has also fostered a fruitful encounter between cultural and border studies: an emerging “border turn” underlines the creation of demarcations as an open, contingent dynamic (Fellner and Nossem 2024; Bürkner 2017).

The notion of “bordering” stresses agency in the establishment or dismantling of borders (Van Houtum et al. 2005), the activities of go-betweens also contributing to border stabilization or transgression. In assessing their porosity or impermeability, it is emphasized that cultural borders are made meaningful by those who experience their effects (Parker 2006, pp. 80–89). Already established as a topic of reflection and research (Newman 2006), the crossing between borders has extended its scope beyond territories or social groups: a “multiscalar” conception of borders (Laine 2016) is applied now to knowledge and cultural spheres (Mignolo 2012). The literature on liminality (van Gennep [1909] 2013; Turner 1974) has circulated categories such as boundary demarcation or contour, signaling limitations and constraints but also highlighting that the study of borders touches upon the construction of identity and otherness, underscoring issues of inclusion and exclusion.

In the case of borders between politics and religion, it is well known that in traditional societies, these two spheres were deeply intertwined in social institutions and as sources of political legitimacy, their separation being only established in the wake of the Enlightenment and the French Revolution. From then on, practices and beliefs outside religious orthodoxy were no longer defined as heresies, and secularization made its way along with equality before the law was introduced with modern constitutionalism (Taylor 2007; Witte 2015). However, it should not be concluded from this that their previous historical trajectory lacked any significant mutual variation. In the lower Middle Ages, the development of more centralized taxing states and coordinated legal systems fostering institutional integration (Ertman 1997; Harding 2002; for Castile, Villacañas Berlanga 2008; Monsalvo Antón 2019, pp. 385–428), together with the reception of classical political philosophy (Skinner 1978), made religion and politics experience changes in their relative status that affected their mutual borders. Ideological investments by Courts on the common good as a source of legitimacy (Kempshall 1999; for Castile, Carrasco Manchado 2019) paved the way for diverse local evolutions in the relationship of politics and religion; further complicated by the 15th-century struggle on how to organize the Church as a political entity (Black 2005; Kern 2019), contingent local outcomes affected the permeability of their borders that were to influence the definition of exclusionary social identities.

Historiography on the early Renaissance stressing the development of political languages and practices autonomous from theological legitimation (Viroli 1992; Pocock 1975) converges here with Pizzorno’s (1987) thesis on politics as a sphere which may expand beyond its established contours, extending its jurisdiction due to its unique capacity for self-reflectivity. The understanding Pizzorno proposes of the political as potentially limitless or absolute implies that its borders shift as politics contracts or expands, while it is also through political processes that new frontiers are set, affecting the relation of the political with other spheres, i.e., that of religion.

Relevant for this article is that Pizzorno’s view of “politics unbound” is linked to a historical account originating in the Middle Ages around the struggle for supremacy between the Papacy and the Empire. The triumph of the former would have implied establishing a kind of theocracy; however, the Empire did not impose itself, rather embedding a long-term dynamic of mutual competition that would eventually give birth to the modern state and citizenship. Our argument finds inspiration in this approach but further historicizes the shifting relations between the political and religious spheres: from the late Middle Ages, the changing interactions of politics and religion contributed to define another sphere emerging in discourse and acquiring its own borders, that of customs.

Customs are to be understood here as a set of practices that refer to evaluative criteria, producing a hierarchy shaping moral distinctions, establishing limits between what is naturalized and what is rejected, accepted or suspicious, while expressing collective goals and purposes defined by groups and communities. Incorporating community customs to the scheme as a sphere is thoroughly justified, as it is widely accepted that mores and customs have links with both religion and politics (with religion: Tönnies [1909] 2014; Bergson [1932] 2013; Wainwright 2005; Hare 2006; Murphy 2011; with politics: Carritt 1935; Ash 1977; Foucault [1969] 2002; Chiffoleau 2010; Catalina Gallego 2020). Such a perspective underpins the discourses widespread in traditional societies where, through significant ritual practices, customs played a role in the definition of membership vis-à-vis other religious identities (Aslan 2005; Denny 1986–1989). Likewise, in the premodern world, customs—usually fixed in customary law, a source of authority legitimized by memory—were at the basis of the relationships of subjects as members of political communities, among themselves and with their rulers.

This overall view needs more specification, however, because there were habits in traditional societies not included in customary law and that, although intermingling with theological precepts, were not the object of distinctive attention by theologians: in particular, those relating to daily routines and practices such as ways of dressing, diets and idioms by subaltern groups in general, and especially confessional minorities. Such habits certainly had social significance: combining stereotypes and prejudices, they allowed us to recognize, distinguish, and often in fact imagine “others”; yet they tended not to be subject to legal regulation since they were not prominent enough to produce community cleavages as did beliefs or the law. Rather they tended to be naturalized, more so as their practitioners were established in the territory for generations and shared other customs and habits with wider local communities subjected to common powers. Our stance is that in the later late Middle Ages, as the relations among religious groups deteriorated in the wake of political transformations that brought about uncertainty and instability, this kind of habit ceased to be “invisible”, taken for granted or regarded as non-conflictive; quite the contrary, daily customs and certain habits eventually became the focus of discourse. This trend was particularly marked in multi-confessional societies and cultures, and within urban environments, where issues of local self-government and integration became prominent.

All this makes the late medieval Crown of Castile a particularly suitable laboratory for research on the changing relations between religion, politics and customs. In such a context, characterized by the expansion of the boundaries of the political over other spheres of community life, the way to study this process is by relating to their political contexts of emergence the speeches by a variety of agents—court nobles and urban privileged, local authorities and royal officials, secular and regular clerics, theologians or preachers—that were intensive through the 15th century in crossing the borders between religion and politics. The effect of their activities would be the emergence of customs as a sphere of discourse of their own, in a process that would eventually produce a redefined hierarchy between politics and religion, and long-term fixing of their respective borders—also with the sphere of customs.

Traditionally, the historiography on judeoconversos in the Iberian Peninsula has been shaped by teleological interpretations that framed the so-called “converso problem” as the inevitable prelude to the Inquisition and the expulsion of minorities, alongside essentialist views that treated converso identity as fixed and ahistorical (Sicroff 1985; Roth 2002; García Arenal 2013, pp. 1–30). These approaches were further reinforced by a concern with assessing the sincerity of converted minorities through an uncritical reliance on inquisitorial documentation (Netanyahu 1995; Kamen [1965] 2023). Since the late 20th century, the influence of cultural studies and historical anthropology has made scholarship more sensitive to understanding identities as situational, fluid and strategic, while placing converts within family, patron–client and urban networks (Gitlitz 2003; Pastore 2003; Nirenberg 2002b; Vidal Doval 2015; Scotto 2019; Pereda and García Arenal 2021). In this light, the persecution of these groups is increasingly interpreted as closely tied to political decisions and power relations. Greater attention has also been paid to specific urban contexts and family trajectories, while comparative perspectives across the Iberian kingdoms, Italy, Maghreb and Flanders have been adopted (Schwartz 2008; Contreras Contreras and Martínez de Codes 2010, pp. 189–207; Bethencourt 2024; Schaub and Sebastiani [2021] 2025). Building on these dynamic, situational and multicausal approaches, a focus on the boundaries between religious, political and customary spheres further challenges functionalist assumptions on the relations between agency and power. By foregrounding such boundaries, this perspective highlights contingencies in the relevant processes and contradictions in the discourse and practices of historical actors.

3. Urban Conflicts for Inclusion and the Crossing of Borders in the First Half of the 15th Century

Since the 14th century, the kingdom of Castile had been undergoing institutional centralization, a process promoting a language on the common good but also social struggles challenging the borders of the sphere of politics. Already in 1369, the establishment of a new dynasty, the Trastamara (1369–1474), took place amid a profound crisis in urban government. Violent conflicts between local groups increasingly organized by estate cleavages had already forced the monarchy to impose in 1345 a reform that abolished neighborhood assemblies and assigned decision-making to perpetual offices (Jara Fuente 2007; Asenjo González 2009, pp. 52–84). Though contributing in the short term to urban pacification, this system—named regimiento—left unsolved how to incorporate the social and confessional complexity of cities and towns into the new local settlement. As urban population grew and economic dynamism increased, from the final decades of the 14th century, Castilian towns became the scene of collective struggles for political incorporation (Sánchez León 2007). Often instigated by the high nobility and the court in their bid for controlling urban government, knights and lawyers organized themselves into bandos linaje, retinues of lineage and factions (Monsalvo Antón 1993; Solórzano Telechea 2014, pp. 183–203; Jara Fuente 2007)—though sometimes envisaging all-encompassing corporations (Sánchez León 2022).

From their own struggles for integration, the Común—formed by taxpayers or pecheros—secured representation in urban governments through elected deputies; despite its political crystallization, the popular estate was however incorporated with a lower status vis-à-vis the privileged knights and lawyers who hegemonized local politics from both outside and within the institutions. The diffusion of the language of politics throughout an expanding public sphere provided the Común with resources for contesting the privileged in their competition for the control of local offices, making conflicts endemic. Outbreaks of violence recurrently overflowed the institutional framework of urban communities, whose social complexity was increased by the coexistence of three religions, two of which embodied subaltern minorities. This singular confessional component of the cities and towns of Castile favored the refraction of polemics over political incorporation and influence towards the religious sphere: through the second half of the 14th century, towns gathering in parliaments or Cortes submitted petitions to the kings protesting the involvement of Jews in usury practices and questioning them as valid witnesses in trials and as retainers by kings and nobles (Suárez Bilbao 2000, pp. 108–21).

Although religion was a primary criterion of their respective legal capacities, and interreligious tensions were recurrent, coexistence has also been fully acknowledged for earlier medieval Castile, manifested in cultural and institutional transfers, interreligious conversions, social interactions and the sharing of customary practices (Castro 1948; Collins and Goodman 2002; Mann et al. [1992] 2007; Soussen 2020). In 1391, this inherited order was suddenly broken, as numerous anti-Jewish massacres spread throughout the kingdom, especially in large cities. The event is considered the starting signal of a dynamic whose arrival point would be the expulsion of the Jews in 1492 (MacKay 1972; Pérez 1993). However, there lies in between a whole century lacking a consistent trend towards the exclusion of minorities, even less so an expansion of the sphere of religion at the expense of the political sphere. The trends initiated in 1391 were of other kinds, revealing a different hierarchy between religion and politics.

Certainly, anti-Judaism in Castile was a legacy of the 14th century, yet it did not intensify with time or reflected widespread consensus from the start, its endurance being greatly due to the ambiguous stance towards religious minorities by Trastamara kings and court favorites. The main outcome of the 1391 pogroms was greater socio-cultural complexity, as there took place massive, forced conversions of Jews to Christianity (Benito Ruano [1976] 2001; Valdeón Baruque 2004; Nirenberg 2002a). Although it was intended to incorporate them into the majority and hegemonic Christian community, the so-called conversos would end up defining a category of their own in discourse on social classifications. However, as opposed to the shrinking population of Jews, for at least one generation, Castilian conversos on the rise were not until the middle of the 15th century exposed to public denigration, less so to segregation or political exclusion. Available studies and inquisitorial testimonies show that, in general, they maintained good relations with their neighbors and shared ceremonies and rites, especially in urban environments, where they held local political positions and religious and royal offices (Haliczer 1997, pp. 240–41, 248; Contreras 1997, p. 290; Muñoz Solla 2009, pp. 207–28). This was so, greatly because many converts were quickly accepted into the upper layers of society, to the point of mixing with an entire cohort of privileged nobles, prelates and lawyers (Márquez Villanueva 1957, pp. 503–15). Successfully incorporated into urban oligarchies and even the ranks of both the lay and secular high nobility, Castilian Jewish converts incarnated the complex matrix of relations between the religious and political spheres that gave advantage to the latter.

As a result, distinctions between Christian believers of different origins were initially of little public relevance. What the crisis of 1391 triggered in the shorter term was rather discourse favoring an institutional reinforcement of the distinctions between the Christian, Jewish and Muslim religious communities. After the pogroms, speeches advocating separation in urban places between confessions made their way, arguing against miscegenation and equating contact between the different religious groups with dangerous contagion. Successful preachings in Castile in 1411 and 1412 by the Valencian priest Vicente Ferrer epitomize this demand for interreligious closure: Ferrer openly denounced spaces of neighborhood interaction, shared rituals, mixed marriages, interconfessional domestic service and common forms of dress, grooming and feeding among members of different religions (Cátedra García 1994; Losada 2013, pp. 603–40; Soussen 2020, pp. 271–95). Yet the transfer of such claims to the legal framework was clearly haphazard: the 1412 Laws of Ayllón stipulating the building of walls separating urban neighborhoods (aljamas for Jews and morerías for mudéjares, Muslims under Christian power), the prohibition of mixed marriages and the imposition of visible signs on the Jews’ garments were suspended as soon as 1419 (Cantera Montenegro 2012, pp. 119–46; Sánchez Sánchez 1993, pp. 195–203).

The inability to impose through legislation customs linked to the beliefs of subjects shows limits in the expansion of the sphere of religion over that of politics, and reveals that the assaults of 1391 and its aftermath measures responded to shorter-term xenophobic refractions in the struggles for both popular and privileged incorporation into the regimiento. As elsewhere in Europe, the transition to the 15th century confirmed the rise of an expanding sphere of politics that in Castile brought about conflicts at the institutional level, acknowledging the fluidity of its borders with the sphere of religion.

A similar trend manifested itself even in the high ranks of the Western Church, with the papal schism and the so-called Conciliar Crisis: deemed the most political moment in the history of the Western Church after the 12th-century Investiture Controversy (Robinson 2015, pp. 268–334; Rollo-Koster 2002), the questioning of the supremacy of the pope over the assembled bishops was another landmark in the effects of an expanding sphere of politics. In Castile in particular, a long-influential framework of ecclesiastical discourse on royal authority had evolved from legitimizing the peninsular conquest as a crusade to providing part of the institutional apparatus of the monarchy1; and yet by the early 15th century, a sphere of politics in expansion was actively competing in public spaces with religious rituals, culminating in the royal entry in 1428 of King Juan II (r. 1406–1454) to the city of Valladolid, where monarchical sacralization was proclaimed without submission to clerical authority (Ruiz 1988; Devaney 2015)2.

From Rome to the local urban settings and through the royal courts, the expansion of the political sphere was reflected in struggles for political incorporation that challenged inherited authorities. In Castile, this context of lingering instability inspired intellectual debates rich in new discourse and lasting in polemics. From the passage to the 15th century onwards, the established differentiation between high and low culture relaxed, giving way to a fluid interweaving between scholarly production oriented to the powerful and privileged groups—especially mirrors of princes and moral treatises now elaborated under both royal and noble patronage—and works directed at popular groups—especially in the form of public preaching, anonymous satirical letters, popular romances and couplets loaded with social and political criticism (Acorssi 2011; Baloup 1995). Some authors even speak of a “public opinion” on the rise in which the religious was giving space to the political (Genet 2014, pp. 23–44; Nieto Soria 2017).

Hegemonized by educated authors adapting Italian Humanism, this cultural trend reflected that, both at the royal court and the urban centers of power, the expansion of politics affected all social groups, though in a variety of ways. Among the lay privileged, it expressed the need to consolidate their status by legitimizing as entailed property the holding of local offices and newly acquired assets (Clavero 1974; Bermejo 1985; Beceiro Pita and Córdoba de la Llave 1990; Devís Márquez 2000). Instead, the clergy intervened in the public sphere as an effect of the emerging struggles for internal hierarchy and influence between its secular and regular branches (Rucquoi 1996, pp. 65–86). Ultimately justified by the need to curtail deviation towards heterodoxy and heresy, competition between reformist currents on the rise (González Sánchez 2017; García de Cortázar 2021) oriented the whole clergy toward increasingly aggressive pastoral action. In turn, these initiatives exposed popular groups to a renewed discourse for persuasion purposes (Carrasco Manchado 2006; Val Valdivieso 2014, pp. 173–92).

Much like converts, some of which entered its ranks, the clergy embodied the complex relations between the religious and political spheres—the difference being in that conversos could not appear as an organized group in the public sphere. This weakness left the public sphere and the streets of Castilian towns clear for xenophobic preachers to elaborate and diffuse a radical, transgressive discourse that recurrently crossed the borders between religion and politics. With their sermons and other practices, these agents were shaping a ground of convergence for those groups who felt their status threatened by the effects of the expansion of the political sphere.

4. The Emergence of the Sphere of Customs as a Marker of Heterodoxy and Otherness

The interpretation above helps explain how the fueling of popular discontent by mendicant orders on the rise decisively contributed to embed anti-Judaism among the lower social class in urban Castile (Cohen 1982; Lawrence 1994; García Serrano 1997; Bautista Pérez 2002; Vose 2011). Moreover, the approach to the role of go-betweens in the crossing of borders concerning the shifting spheres of religion and politics also allows us to shed light on the mid-15th-century event considered the turning point towards social and institutional exclusion of converted Christians: the banning of conversos from serving as aldermen and public notaries in the city of Toledo, decreed by the alcalde mayor (appeal judge) Pero Sarmiento in 1449. Considered the precedent of the statutes of blood cleanliness (limpieza de sangre) and of the establishment of the Inquisition (Hernández Franco 2011), Sarmiento’s Sentencia-estatuto was first implemented in a very singular locality and under extreme political circumstances.

Toledo was a royal city that hosted the largest Jewish aljama on the peninsula, as well as an important community of Muslims mudéjares—having been a center for the translation of Islamic and Jewish culture since the 12th century. The town was also the seat of the most extensive ecclesiastical jurisdiction in the kingdom, whose archbishops stood out throughout the century for their influence over the royal court. Moreover, having preserved self-management of its minority religious communities—which included traditions and rituals practiced by a group of Christian mozárabes inherited from the pre-conquest period, with liturgical and legal implications (Benito Ruano 1961; Molénat 2019, pp. 385–405)—Toledo had been delayed in establishing the regimiento: it had already been introduced in the 15th century, which suggests that the difficulties in incorporating its various social constituencies into the local institutional order were more pressing.

Added to these particularities is the political context of Sarmiento’s sentence statute. The event occurred around a crisis in the relations between the monarchy and large segments of the high nobility pressing against the king’s favorite Álvaro de Luna (1390–1453). The struggle was also sequel to an open confrontation between the prince, future king Enrique IV (1425–1474), and his still reigning father Juan II, who ordered his client aldermen to prevent Pero Sarmiento from assuming upper military and judicial local authority. In turn, Sarmiento mobilized against the king sectors of the taxpayers (the Común) (López Gómez 2021). Among the aldermen were Jewish converts who had managed to attain these and other offices of the city government through their local influence or as retainers of the king.

To justify the persecution and expropriation of the convert aldermen, Sarmiento counted on available ideologues accustomed to crossing with their discourse the borders between the religious and political spheres. Bachelor Marcos García de Mora (d. 1449) and two of the cathedral’s canons framed their arguments in theological rhetoric, offering a vision of converts that drew on political referents (González Rolán and Saquero Suárez-Somonte 2012, pp. XVII–XXVIII; Sicroff 1985). They presented conversos as dishonest subjects who should be persecuted because they practiced their unorthodox rites underground, concealed from public spaces and without institutional monitoring (Cantera Montenegro 2008, pp. 297–326; Benito Ruano [1976] 2001). In their discourse, converts were stigmatized as infidels and accused of heresy, first denigrated as traitors to the monarchical rule, which legitimized the calling for a combination of political and ecclesiastical interventions in the form of an inquisition (pesquisa) (Cavallero 2012, pp. 11–35). Following these guidelines, the local clergy conducted an alleged investigation in Toledo, which resulted in the torture and execution of several converts and the confiscation of their property. With their final expulsion, the city was alienated from loyalty to the monarch, forcing the crisis reach a constitutional dimension, reactivating the local tradition of political autonomy—the exclusion of converts being accordingly legitimized as not simply a judicial verdict but also a statute or piece of legislation (Round 1966; López Gómez 2014).

Producing discourse against a minority of Christians by giving primacy to political arguments was not the only remarkable feature of the Toledo ideologues: García de Mora’s theses also isolated daily ceremonies as an essential criterion for distinguishing the orthodox faithful from heterodoxy. To justify the exclusion from municipal offices of the New Christians, the ideology of the rebels led by Pero Sarmiento pointed to a whole series of social customs that their propagandists discursively linked to rituals and precepts from the much-rejected religion of the Jews. This view took advantage of a long tradition of metaphysical tropes that Christian theology had distilled for centuries, reinforcing their essentialist profile. The 1449 anti-convert publicists reinterpreted this heritage, claiming that culture, appearance and habits made up a people, the Jew, through whose veins ran a blood that was inextricable from their nature and their creed. This argument was reinforced by importing the notions of gens and natio from the ongoing discourse on the transmission of privileged property through blood and ancestors, mixing it with Biblical and Talmudic notions, and adding biological connotations—the resulting combination being now applied to confessional minorities through the semantics of the polysemic term linage (Nirenberg 2002b, pp. 3–41; Soussen 2020, pp. 254–69; Schaub and Sebastiani [2021] 2025, pp. 25–89). The “Jewish lineage” thus ceased to qualify the followers of a religion and came to denote a socio-cultural group whose specific character, transmitted by blood, remained indelibly in their successors converted to Christianity.

The novelty of the 1449 crisis was therefore not, as argued by a long historiographic tradition (Benito Ruano [1976] 2001; Round 1966; Valdeón Baruque 2004; López Gómez 2014), a discourse reordering the hierarchy between religion and politics in favor of the former. Despite being deployed for distinguishing those “pure” Christians who followed the precepts of religious orthodoxy from “others”, it brought about the shaping of social customs and rites as an emerging sphere of community life.

In the shorter term, however, the arguments put forward by the 1449 rebels of Toledo were so disruptive that they triggered a flood of responses by other, competing ideologues of similar clerical and legal background. Elaborated by the main theologians of the period, the discourse sponsored by the Court was also transgressive, though offering an inverse emphasis on political and religious referents which revealed that the expansion of the sphere of politics had reached a limit. Toledo had already gone back into royal control, and King Juan II commissioned one of his theologians to deliver a sermon which opened with a political statement: the rebels had sought to place themselves above the established authorities, breaking their loyalty to the monarch (González Rolán and Saquero Suárez-Somonte 2012). As the speech progressed, however, the preacher introduced a theological argument: peaceful coexistence in the Castilian cities had become so hazardous that a supplement was needed which could only be provided by the Church, whose function was to ensure unity beyond the unstable social and political situation (Sánchez León 2021). Given that the Toledo rebels had challenged the Church, they should be considered heresiarchs and punished by ecclesiastical authority.

The restoration of peace was achieved at the cost of producing a discourse that entailed a reordering of the relations between the political and religious spheres in favor of the latter. In the following months, reputed members of the high clergy such as Alonso de Cartagena (1384–1456), Lope de Barrientos (1382–1469) and Juan de Torquemada (1388–1468), among others, became involved in the debate. Most of them of converso origin, they all contributed to outline the thesis that, through baptism, the Christian faithful made up for social unity: converting and welcoming all kinds of people had been the great novelty that contrasted Christianity with Judaism; therefore, any discrimination against neophytes due to their religious origin, lineage or nation should be considered schismatic and heretical (Rosenstock 2002; Soussen 2020, pp. 279–87; Sicroff 1985). The struggle to define the concept of heresy had a profound impact on the relationship between the realms of politics, religion and social customs in the second half of the 15th century.

With the intervention during the controversy of Pope Nicholas V (1447–1455), who supported the Crown and the initiatives by the clerical hierarchy, the crisis seemed to be overcome. However, it was at a great cost, not only to turn upside down the discourse favoring politics over religion but also to assume the epistemic framework of the rebels, focused on the role of daily customs and habits. In effect, to counter the anti-convert charge of 1449, orthodox theologians defended that such practices were to be acknowledged, though not considered inherited from ancestors but rather expressing a pastoral failure: converts had only been superficially evangelized and needed time to relinquish their bad habits through proper preaching.

The ultimate resolution to the issue was thus placed in the hands of monks and priests, who were increasingly pressing the sphere of politics with their religious discourse; moreover, it was also made dependent on the evolution of a quite contingent and volatile political landscape. During the 1450s and 1460s, as the struggles for influence resurfaced both in urban environments and the Court, disturbances became an alibi for the discursive refraction of wider social and political conflicts towards a focus on the status of confessional minorities. Jewish communities reacted by increasingly closing themselves around the protection of their cultural customs, law and traditions, while the kind of discursive questioning of the New Christians initiated in Toledo started to be replicated in other Castilian towns.

The chances to stop or even slow down this trend by more moderate and convivial members of the clergy were limited: remaining self-secluded within the field of theology, in their discourse, daily customs by conversos were initially not addressed as a public threat to be judged harshly but rather admonished by priests exercising Christian charity in private as with any other believer. With time, however, a restless context forced these ideologues to acknowledge that everyday differences among confessional groups had begun to compromise communal peace, constantly reviving a subterranean ferment of political conflict that menaced the basic harmony of complex urban environments—and ultimately the concord of the social body in the entire kingdom (Nieto Soria 2010, pp. 37–62; Carrasco Manchado 2011, pp. 613–52).

As they all delved further into the question of religious rites and customs, both radical and moderate clerks shared a consensus around the Church as the only legitimized institution that could guarantee the unity of Christians. However, this overall agreement came with the assumption that confessional unity demanded uniformity of practice among all believers, on one hand, and on the other, the prohibition of daily contact with the other cultural and religious communities to prevent them from spreading their own customs. Supporters of the 1449 discourse had in the short term been politically defeated; however, in the following context, the tropes aired by the Toledo rebels had extended, orienting public controversies towards the emerging sphere of customs. In the meantime, the earlier Jew and the later converso issues were being fused in all available discourse.

5. Reconfiguring Boundaries: The Expulsion of Jews and the Stigmatization of Conversos

The accession to the throne of Enrique IV (r. 1454–1474) did not alter the direction of this process, but rather accelerated some of its trends and further outlined its underlying factors. From the beginning of 1460s, political instability escalated into open civil war (1465–1468), reopening once again between 1475 and 1479 over the succession to the throne following the king’s death. Orchestrated by the opposition faction of the nobility, propaganda against Enrique IV accused him of adopting Islamic habits and dressings, and of being surrounded by Jew and Muslim retainers who were holding him hostage at the Court. Amid important urban and popular mobilizations also against the abuses of the nobles, the authority of the monarchy was openly questioned throughout the whole kingdom. In the 1460s and 1470s, as the political sphere deteriorated, unsolved struggles for local governance and urban political autonomy increased the opportunities for scenarios like Toledo in 1449, favoring the manipulation of popular discontent against the converts in large cities such as Burgos, Ciudad Real, Segovia, Toledo, Seville and Córdoba (Gitlitz 2003; Pérez 1993).

Struggles among regular and secular clergy reflected the hegemony of radicals over moderates. Factions within the Church became increasingly polarized under pressure from the most militant mendicant currents, the Observant Franciscans, a reformist and rigorist order for whose members’ daily routines and customs were of crucial importance. The inquisition conducted in Toledo in 1461–62 by Hieronymite friars highlighted the Franciscans’ use of religious sermons to stir up the faithful against minorities and neophytes (Bautista Pérez 2002). The former accused the latter of giving credence to rumors and gossip, preaching lies about circumcision and other Jewish practices among conversos without providing evidence, igniting unrest and promoting violence amongst Christians in the city. They also slandered the king, the bishops and the nobles for failing to suppress the supposed hidden threat posed by Judaizers, in short, inventing a non-existent problem.

Behind these conflicting positions, discourse reflecting the expansion of the religious sphere was consolidating shared assumptions of converts as suspicious Christian believers. This trend is clear in the publication of two treatises—Lumen ad revelationem gentium by the Hieronymite prior Alonso de Oropesa (1464) (Sicroff 1981) and Fortalitium Fidei by the Franciscan friar Alonso de Espina (1465) (Cavallero 2014)—that epitomize the growing polarization among clerical polemics. Both authors were prominent figures at the Court of Enrique IV and charismatic preachers; while the latter depicted faith as a fortress under siege by both Jews, Muslims and converts, and claimed for seasoned fighters to defend it (Cavallero 2014, pp. 117–62; McMichael 2007, pp. 271–304; Vidal Doval 2015), the former admitted that there were conversos who, even if not because of their nature or religious origin, maintained their inherited mores (Sicroff 1981, pp. 315–33). Certainly, rather than condemning all the descendants of a nation, Oropesa claimed that identifying and rooting out the wrongdoers should not be based on their blood but rather on their deeds; however, despite openly defending that customs were mere cultural routines with nothing to do with beliefs, Oropesa’s view that there were believers who remained Judaizers fixed the focus on converts as potential heretics to be excluded.

Besides stark differences in viewpoints, such controversies further contributed to distinguishing daily rites and practices as a sphere of its own within late medieval Castilian culture; yet its borders with the sphere of religion remained highly porous, to the advantage of radical discourse. Those clerical intellectual elites favorable to the integration of converts were placed on the defensive when facing the essentialist proposals initiated by the discourse of Toledo rebels and continued by Franciscans, allowing their more aggressive counterparts to argue that certain daily habits and personal features had to be regarded as intimately linked to theological precepts of the religious minorities (Scotto 2019, pp. 291–327). Dissemination in popular and courtly circles of such preconceptions made it easier for the anti-convert imaginary to undergo a reformulation of the relations between habits and beliefs that inverted the inherited explanatory rationale: New Christians were defined as different despite coming from families baptized for two or three generations. Customs were to be deemed as inherited from ancestors, and so inseparable from lineage and blood. Accordingly, neophytes of Jewish origin were, first and foremost, Jews, and only secondarily Christians, as their lineage made baptism ineffective.

With this essentialist turn, habits were functioning as a means for defining the boundaries between religious communities, offering a set of diffuse and increasingly distorted descriptions of confessional minorities that prescribed a threatening status for the already subaltern and marginalized Jews and Muslims, while reinforcing the growing stereotypes of conversos in a vicious circle of mutual feeding. As catechisms and manuals designed to identify Judaizers lumped together without discriminating Jewish religious ceremonies with long-established local everyday routines, segregation reappeared reinforced in discourse. From the 1460s, in sermons and pastoral literature, Jewish traditions and customs were presented as contagious and a source of sin; accordingly, all conversations and contact with members of this religious minority were inadvisable. In this rhetoric, the lack of distinction in external appearance—mainly in clothing and the arrangement of hair and beard—was deemed an aggravating factor that hampered the separation between confessional groups. Even those who defended the right of converts to be considered full Christians found themselves increasingly admitting that their full integration required not only the segregation (apartamiento) of Jews and Muslims but also renunciation by conversos of all traces of their inherited traditions to prevent these from influencing the habits of both old and new Christians.

Emerging claims for the enforcement of old papal legislation and the 1412 Leyes de Ayllón show that, besides invigorating religious discourse, any solution to the religious issue touched on its part upon the political sphere. Once essentialist images were fixed, changing customs or beliefs could not be trusted as a successful religious policy (Nirenberg 2002b; Pereda and García Arenal 2021, pp. 11–33). The situation called for urgent intervention from above: as Jews were portrayed as a threat whose aim was the destruction of Christianity, as the contexts of the Talmud supposedly confirmed, the friars and the people were obliged to mobilize if the authorities failed to do so.

This discursive outcome was inseparable from other wider contemporary political events in Castile and the entire Christendom (Millet 2009). From the 1470s, the failure of conciliarism in Rome definitively enthroned the monarchical solution within the central power of the Church; on its part, the end of the civil wars in 1479 allowed the new Iberian monarchs, Isabel of Castile (r. 1474–1504) and his consort Fernando of Aragón (r. 1474–1516) to reactivate the conquest of the Nasrid kingdom of Granada, presenting it as a crusade that galvanized transcendentalist goals for the entire community to legitimate their political program (Carrasco Manchado 2017, pp. 559–92). In their effort to recover royal authority, the new monarchs soon decided to intervene over the three main conflictive groups—the clergy, the secular nobility and the urban oligarchies—in ways that further contributed to target religious minorities: by cleansing the urban offices of conversos for the establishment of urban oligarchies on a more peaceful setting, by securing the entailed assets of magnates and the gentry through legislation based on blood that further consolidated essentialist images of family groups, and by mobilizing the clergy as a whole towards pastoral activities to appeal to popular sentiments. In its wake, fears of wider collective reach were ignited by pointing to an enormous threat, unknown and lurking, stemming from the rites that Judaizers allegedly practiced hidden from the public space—including the desecration of the Eucharist and the ritual sacrifice of children (Théry 2009, pp. 201–43; 2017, pp. 83–150; Chiffoleau 2010).

In this successful definition of an interior enemy, the spheres of religion, politics and customs showed an extreme permeability, their interborder crossings in discourse serving now the common purpose of legitimating converso exclusion. For some, cristianos nuevos could only legitimately claim a public presence in the community and participate in the institutions if they were willing to carry out a militant display of the habits imposed by Old Christian orthodoxy. For others, renouncing inherited customs was not a sufficient condition to be accepted as full members of the respublica christiana: customs, lineage, rituals, blood and appearance constituted a blemish not only on moral quality but also on the religious faith of the converts. Miscegenation was a by-product of the blending of the religious with a heritage notion, two elements different in nature that had given rise to the greatest of impurities and monstrosities, disqualifying conversos from holding public office in the cities or enjoying any legal authority over Old Christians. Provided that an insurmountable social divide had emerged between old and new Christians, the fate of Jews was obviously cast.

Behind this social and cultural process, a new hierarchy between the spheres of politics, religion and custom was established. In the case of the relations of customs with religion, a decisive step was taken in the work by Hyeronimite bishop Hernando de Talavera, who in the early 1480s engaged in a polemic against an anonymous Judaising writer from Seville. He wrote a treaty, Católica Impugnación, that reduced relevant customs to that incumbent to religious practices, such as resting on Saturday, eating halal meat, consuming bread unleavened or kosher food, burying the deceased on the outskirts of the town, washing the dead, rejecting religious images and practicing circumcision (Iannuzzi 2009; Pascua Echegaray 2021). Revisiting the old Patristic notion that Christianity had accepted only the “moral laws” of Judaism, but had rejected and renewed the “judicial and ceremonial laws”, Talavera concludes that the orthodox Christian should never follow customs and ceremonies associated with Judaism. Adopted by competing lay and clerical agitators, the rhetoric on customs soon penetrated other registers and genres, presenting the harassment of Jews, Muslims and conversos alike as legitimate self-defensive reactions (Gitlitz 2003, pp. 109–36; Vidal Doval 2015; Cohen 1982).

On its part, a new relation between religion and politics was established that did not revert towards the past hierarchy from the early medieval period, but was rather innovatively reconfigured into a new complex, as expressed in well-known institutional sequels: the transfer of the Roman Inquisition to the monarchy in 1480 and the expulsion of Jews in 1492. Once the impossibility of conversion had been acknowledged, the translation of antisemitic ideas into policy took shape in two complementary directions: first, the demand that ecclesiastical authorities receive support from the Crown in placing Jewish converts definitively under their jurisdiction (Kamen [1965] 2023; Roth 2002; Netanyahu 1995); and second, the active involvement of the monarchy in assisting the Church in the legal suppression of minority groups. Far from constituting a merely confused or hybrid arrangement, primacy remained firmly within the religious sphere, whose representatives were legitimized to articulate the ideological framework that ensured the cohesion of the political body while simultaneously identifying heretics as enemies of the community subject to repression (Rosenstock 2002; Nirenberg 2007; Cavallero 2012). However, to the extent that the collective participation of conversos in the community was ultimately blocked by excluding them from public offices, the new legitimacy included the autonomy developed by the sphere of politics during the whole previous century, reinforcing the status of the central apparatus of the monarchy. From then on, clerical and lay ideologues would recurrently cross between the two spheres, but reproduce rather stable mutual borders.

The main effect of such a new hierarchy between religion and politics was the exclusion of those accused of having converso origin. From then on, converts could not aspire to receive recognition as equal to other subjects under the law, being at best defined by default. Denial of their confessional identity would be the practice of anonymous denunciation enabled by the Inquisition, which on its part made customs and habits functional for legitimating the detection and repression of dissidence, whether strictly religious, moral or widely ideological. In the short term, the dominant discourse of alterity founded on ontological images of “nation and race” quickly became part of the accusatory economy that justified the failure of evangelizing efforts carried out over New Christians and the expansion of legislation enforcing purity of blood (Schaub and Sebastiani [2021] 2025, pp. 91–152).

If theological controversies had since the middle of the 15th century been expanding the sphere of customs over that of religion, the official ideology of a reinforced monarchy came, in turn, to place customs under the normative jurisdiction and social control provided by the political sphere, while appropriating goals taken from the sphere of religion. Since the 1480s, theologians, now from positions very different from those of the previous generation, subordinated community customs to doctrinal precepts. The long-standing call for spiritual unity had turned into social uniformity. By reaction, however, among conversos themselves, routines and appearance were upheld as ways of expressing their identity, giving rise to new forms of resistance against the Old Christian society (Gitlitz 2003; Barrios Aguilera 2008; Iannuzzi 2019, pp. 430–60; Rayo Muñoz 2023; Pascua Echegaray 2024, pp. 43–46; Kimmel 2015). Daily habits had become the vehicle for regulating core aspects of social life, both legal–public and domestic–spiritual, and both among the dominant powers and the resistant minorities.

6. Conclusions: Naturalization and Long-Term Definition of Customs

The 15th century witnessed processes of alteration in the relations between religion and politics throughout Europe, with various agents crossing their respective borders and producing varied consequences in each geographical setting. In the Italy of the city states, from Leonardo Bruni to Niccolò Machiavelli, several generations of Humanists consolidated the autonomy of the political sphere, ultimately giving shape to an inclusive citizenship (Hankins 2019); although their discourse included tropes of religious affiliation, such as the myth of a primitive community of believers free from moral corruption and inequality, these were placed at the service of emerging conceptions of political virtue (Pocock 1975). Since the beginning of the 16th century, with the Protestant Reformation, long-term questioning of Roman papal authority gave way in many other parts of Europe to a scenario of profound shifting in the sphere of religion regarding the inherited boundaries between orthodoxy and heresy, opening up a context of embedded conflicts between incompatible versions of Christianity (Lindberg 2021); yet, despite the centrality this gave to the religious sphere, from the cities of Switzerland and the Netherlands to England, the externalities derived from such controversies often escalated into constitutional crises that ultimately expanded politics over the other spheres of community life (Cressy 2006; Berman 2009)—including that of customs (Gorski 2003).

Different outcomes, in which the borders between religion and politics were reshaped in a way that implied a complex intertwinement between religious legitimacy and political expansion, characterized the Hispanic so-called “Catholic Monarchy” for the rest of the Early Modern period. In this article, we have described the process that led the Hispanic Monarchy to block the consolidation of inclusive political communities that could have otherwise evolved towards citizenship. It instead imposed a confessional orthodoxy that denied recognition to entire parts of the Christian majority itself for the simple fact of being neophyte converts from Judaism or Islam. In Castile, as in Europe, the drive for reform of the Church and society hung over all the seats of power. However, a traumatic event in the collective memory—the massacres of Jewish communities in 1391—which triggered unprecedented upward social mobility of the converts simultaneously at the highest levels of power within both central and local institutions, led to a redefinition of the doctrinal framework of debate in which many actors belonging to different denominations—and thus subject to different religious laws—competed, with the unintended consequence that the most rigorous and ascetic positions established the new boundaries of classification in a sphere of significant future developments: society.

The case shows that alterations in the boundaries between religion and politics have effects reaching beyond their respective spheres, spilling over into other dimensions of community life, such as customs, habits and physical appearance. The reconstruction of the process through which mores came to be subjected to increasingly strong legislative regulation and institutional and social surveillance can only be understood by analyzing, from the perspectives of the political and religious spheres, the discursive elements and social actors that crossed their boundaries in specific historical cases. This has implications for other areas of action, such as social discipline, and shifts the boundaries between the elements that can be employed in different discursive contexts, which in turn increases the possibilities of active transgression and the crossing of borders by agents, no matter how defined and instituted they appear.

However, the porosity of the border between customs and politics was maintained, which helps us understand why the debate on the expulsion of the moriscos (Muslims converted to Christianity) and the boundaries between their culture and their religious beliefs remained a priority topic of discussion at 16th-century ecclesiastical councils (Kimmel 2015, pp. 37–74). Following the conquest of the Nasrid kingdom of Granada, Muslims forced to convert to Christianity in 1502 suffered marginalization, exclusion and eventually expulsion in 1610. Even more clearly than judeoconversos in the 15th century, 16th-century moriscos were retaliated against for their appearance, customs and way of life. Their communities were dismantled through physical violence and legislation designed to suppress ordinary daily customs: using Arabic, playing certain musical instruments, decorating their hands with henna or wearing specific dresses (Barrios Aguilera 2008; Coleman 2013; Rayo Muñoz 2023, pp. 1091–118). It is no coincidence that the strongest defense of the Muslim converts presented by the cultivated morisco Francisco Núñez Muley in his Memorial at the royal court in 1566 was based on the argument that their customs did not indicate heresy or treason, but were merely local traditions, as was the case in so many other Christian regions.

The general reflection for different European kingdoms is that the entire process described is ultimately explained by understanding that only politics has a genuine “reflexive power” (Pizzorno 1987) that allows it, depending on changing contexts and through discursive and institutional transgression, to redefine its own boundaries and limits, thus expanding or contracting its own sphere, and in doing so affecting its borders with other spheres of community life. It is our belief that Western historians and intellectuals have not weighed enough on the relevance of customs in the premodern period, because the societies they have studied were much more uniform in habits compared to those from the Iberian Peninsula hosting large amounts of religious minorities established in the territory for generations. When they have done so, they have focused on the ruling classes, dispatching the role of ethnic and religious minorities (Elias [1978] 2000). Here, we have tried to bring a more political explanation to the psychogenesis of moral orthodoxies.

To conclude, and linking back to the Castilian case, following the recognition of customs and habits, politics ultimately expanded into the religious sphere; however, in a process led by religious inquisitorial authorities, politics itself was being reduced to mere institutional management, explicitly emptied of controversy, stripping the capacity for deliberative participation from subjects, now reduced to objects of administration; that is, politics had become rather “impolitics” (Esposito 2015). Seen this way, Jews and converts from Islam and Judaism had a common foundation, their deformity deriving from their shared biological nature materialized in blood, which made them by nature reluctant to abandon their untruthful “second nature” at the moral level. Discourse on origin and lineage fitted in well with classical and medieval assumptions that customs were characterized as a “second nature” (Kelley 1990, pp. 131–36); however, it was made into something much greater and anew.

To recapitulate, the arguments underlying this study assume that the transition from the medieval to the Early Modern state was neither linear nor uniform, that these trajectories have been diverse in Europe and have largely depended on the interplay of discourses belonging to different spheres—the political and the religious—and, finally, that, as a consequence of these interactions, discourses of exclusion and stigmatization were articulated as fundamentally embedded in a new sphere—customs and everyday habits—associated with an emerging conception of the social. The Hispanic obsession with blood purity during the Early Modern period represents the culmination of a century of debates concerning customs. Underlying the sudden shift toward blood as a selection mechanism for admission into corporate bodies and access to political office lay the essentialization of customs and appearance, to the extent that they came to be conceived as naturalized inheritances.