A > 10-km-thick basin formed in Tertiary to Quaternary times in front and overlapping with the south-east Carpathians. The Focşani Depression is part of this system and overlies the Vrancea seismogenetic volume, thought to correspond to the remnants of the continental slab subducted beneath the Carpathians. Slab detachment and its lateral migration are considered to control vertical movements in the area. We present the first complete analysis of subsidence patterns in the Depression and derive a substantially different picture. The strongest subsidence is Sarmatian in age, coeval with the main nappe emplacement events. Subsequently, subsidence did not stop and persisted until present times despite cessation of thrusting. The main depocentre remained the Focşani Depression and no significant lateral migration is detected. Post-Sarmatian subsidence is contemporaneous with major exhumation/erosion in the Carpathians. The evolution of the basin is associated with a combination of vertical and far-field horizontal stresses, and its position is controlled by pre-existing lithospheric heterogeneities.