Contrasting views exist in the literature in regard of the evolution of metamorphic rocks in the southeastern Pohorje Mountains (Mts), located in the southeastern Eastern Alps. Major debated points are whether micaschists have experienced ultrahigh‐pressure metamorphism in the Late Cretaceous (Eo‐Alpine) and whether they were continuously exhumed or experienced a multiple subduction‐exhumation process from that time on. Therefore, we studied micaschist sample 18Slo39 with two generations of garnet and phengitic muscovite from this area. Our detailed study of this rock included petrographic observations, chemical analyses of minerals with the electron microprobe, pseudosection modeling, conventional geothermometry, and monazite in‐situ U‐Th‐Pb dating using laser‐ablation ICP mass spectrometry. The following results were obtained: The studied micaschist was subject to a peak‐pressure of 1.31±0.14 GPa at 603±26 °C in Eo‐Alpine times: 90.62±2.78 (2σ) Ma (Stage I). Contact metamorphism at pressure‐temperature conditions of 0.66±0.10 GPa and 577±23 °C was induced by the intrusion of the Pohorje pluton (Stage III). We determined an early Miocene age of 18.33±0.43 (2σ) Ma for this intrusion. Based on this study and the previously reported data for a micaschist (16Slo12) taken in the vicinity of sa 18Slo39, a geodynamic model is proposed for the region of the Pohorje Mts considering Eo‐Alpine subduction of oceanic crust and European continental crust, of which the micaschist was part of. Another high‐pressure event in the Eocene (Stage II) was the result of intracontinental subduction due to transpression by the Periadriatic fault system which separates the Eastern Alps from the Southern Alps. This type of subduction gave rise to magma generation and ascent to form the Pohorje pluton, which caused contact metamorphism in its vicinity.