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Many convergent orogens, such as the eastern European Alps, display an asymmetric doubly vergent wedge geometry. In doubly vergent orogens, deepest exhumation occurs above the retro‐wedge. Deep‐seismic interpretations depict the European plate dipping beneath the Adriatic, suggesting the pro‐wedge location on the north side of the orogen. Our new thermochronometer data across the Eastern Alps confirm distinct shifts in the locus of exhumation associated with orogen‐scale structural reorganizations. Most importantly, we find a general Mid‐Miocene shift in exhumation (in the Tauern Window and the Southern Alps) and focus of modern seismicity across the Southern Alps. Taken together, these observations suggest a subduction polarity reversal at least since the Mid‐Miocene such that the present‐day pro‐wedge is located on the south side of the Alps. We propose a transient tectonic state of a slow‐and‐ongoing slab reversal coeval with motion along the Tauern Ramp, consistent with a present‐day northward migration of drainage divides. Plain Language Summary: When tectonic plates collide, they bend downwards and form two lithospheric wedges dipping in opposite directions, such as in the Eastern Alps. We present new crustal cooling data along a transect in the Eastern Alps confirming that surface rocks across the central Tauern Window originated from the deepest structural levels along the transect. South of the Tauern Window rocks were exhumed from higher depths compared to those north of it and were exhumed more recently, while seismic activity is also focused across the Southern Alps. These observations suggest a subduction polarity reversal because they are inconsistent with the original southern and northern locations of overriding and subducting plates, respectively, >15 million years ago. This interpretation is contrary to lithosphere‐scale tomography that shows no change in subduction polarity. Therefore, we propose a transient tectonic state, that is, a slow‐and‐ongoing subduction polarity reversal that initiated when Tauern Window rocks began their steep ascent to the surface along a deep‐seated fault known as the Tauern Ramp. This study bridges observations in the mantle, crust and on the surface over geologic time. Key Points: Thermochronologic data in the Eastern Alps is consistent with a transient tectonic state toward complete slab reversalThe pro‐wedge has switched from north to south of the Periadriatic Fault along TRANSALPMid‐Miocene motion along the Tauern Ramp is the consequence of slab‐reversal [ABSTRACT FROM AUTHOR]

Buoyancy forces associated with subducting lithosphere control the dynamics of convergent margins. In the postcollisional stage these forces are significantly reduced, yet mountain building and seismicity are ongoing, albeit at lower rates. We leverage advances of a newly developed seismo‐thermo‐mechanical modeling approach to simulate tectonic and seismicity processes in a self‐driven subduction and continental collision setting. We demonstrate that the rearrangement of forces due to slab breakoff, in the postcollisional stage, causes bending and rollback of the residual slab, suction forces, and mantle traction at the base of the upper plate, while stress coupling transfers to the shallow crust. Our results provide an explanation for the postcollisional evolution of the Central Alps, where the so‐called Slab Rollback Orogeny model explains the slow yet persistent upper plate advance, the height of the mountain range, and a seismicity pattern consistent with the different tectonic regimes throughout the orogen. Plain Language Summary: A long‐standing debate in tectonophysics evolves around whether vertical or horizontal forces are the primary drivers of mountain building processes. Here we explore this problem using 2‐D numerical models in a generic subduction and continental collision setting. Our results show how the postcollisional evolution of the orogen is controlled by a slow, but persistent, sinking and bending of the postbreakoff residual slab. The resulting seismicity pattern shows a broad pattern of different style of faulting, which are consistent with the local tectonic regimes. We find good correlations between our numerical results and the previously conflicting tectonic observations in the Central Alps and the adjacent foreland basin. Our results thus support the hypothesis that the postbreakoff remaining slab exerts a first‐order control on the motions and deformations of collisional orogens. Key Points: Two‐dimensional seismo‐thermo‐mechanical modeling is performed to investigate the driving forces during the postcollisional stagesPost‐breakoff residual slab proves sufficient to sustain slab rollback and retreat of the entire orogenThe proposed scenario is consistent with the postcollisional seismotectonic evolution of the central European Alps [ABSTRACT FROM AUTHOR]