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The Eastern Carpathians are thrust to the east and north over their Eastern European foreland, tectonically covering it over an area several hundred kilometers across. Information about the nature of the underthrust part of the Carpathian foreland can be obtained from the rock fragments preserved in the sedimentary successions of the Carpathian fold and thrust belt, specifically in the Outer Dacides and the Moldavides. Fragments of felsic rocks occurring within the sedimentary units of the Upper Cretaceous successions of the Moldavides have long been attributed to the Cuman Cordillera—an intrabasinal ridge in the Eastern Outer Carpathians. This work is the first complex geochemical and geochronological study on the exotic igneous clasts of the Cuman Cordillera. Igneous clasts from the southern part of the Moldavides (Variegated clay nappe/formation) are investigated here. They include mainly granites and rhyolites. Phaneritic rocks are composed of cumulus plagioclase, albite, amphibole and biotite, and intercumulus quartz and potassium feldspar, with apatite, magnetite, sphene, and zircon as main accessories, while the porphyritic rocks have a mineral assemblage similar to that mentioned above, displayed in a porphyritic texture with a usually crystallized groundmass. SHRIMP U-Pb zircon dating indicated the 583–597 Ma age interval for magma crystallization. Based on calcareous nannofossils, the depositional age of the investigated igneous clasts is Cenomanian to Maastrichtian, implying that the Cuman Cordillera was an emerged piece of land, herein an active source of sediments in the flysch basin for at least 40 Ma, from the Early Cretaceous (Aptian) to the Late Cretaceous (Maastrichtian). The intrusive and subvolcanic rocks show similar trends for trace and major elements, evincing their comagmatic nature. The enrichment in LILE and LREE relative to HFSE and HREE, as well as the element anomalies (e.g., negative Nb, Ta, and Eu and positive Rb, Ba, K, and Pb) suggest a convergent continental plate margin tectonic setting. Mineral chemistry suggests magma crystallization in relatively oxic conditions (magnetite series), during ascent within a depth of 15 km to 5 km. The igneous rocks attributed to the Cuman ridge display compositional and geochronological features similar to Brno and Thaya batholiths in the Brunovistulian terrane, which could be a piece of the Carpathian foreland not covered by the Tertiary thrusts. Our data confirm the non-Carpathian origin of the igneous clasts, revealing a Neoproterozoic history of the Carpathian foreland units, which include a Cadomian/Pan-African continental arc, exposed mainly during the Late Cretaceous as an intrabasinal island of the Alpine Tethys, traditionally known as the Cuman Cordillera. Full article