Military relations have always been tense between these two Caucasus countries following the dismemberment of the Soviet Union. The bone of contention is the Nagorno-Karabakh province, which is an Azeri enclave. It was made an autonomous oblast (administrative region) of Azerbaijan by Joseph Stalin in 1923. In the run-up to the fall of the Soviet Union in 1989, the Armenians living in Karabakh started to ask for the transfer of the province from Azerbaijan to Armenia. Full-fledged military confrontations took place between the late 1980s and May 1994.