Following the politics of "glasnost", initiated by Mikhail Gorbachev, civil unrest and ethnic strife grew in various regions of the Soviet Union, including Nagorno-Karabakh, an autonomous region of the Azerbaijan SSR. The disturbances in Azerbaijan, in response to Moscow's indifference to an already heated conflict, resulted in calls for independence and secession, which culminated in the Black January events in Baku. Later in 1990, the Supreme Council of the Azerbaijan SSR dropped the words "Soviet Socialist" from the title, adopted the "Declaration of Sovereignty of the Azerbaijan Republic" and restored the flag of the Azerbaijan Democratic Republic as the state flag. As a consequence of the failed coup which occurred in August in Moscow, on 18 October 1991, the Supreme Council of Azerbaijan adopted a Declaration of Independence which was affirmed by a nationwide referendum in December 1991, while the Soviet Union officially ceased to exist on 26 December 1991. The country now celebrates its Independence Day on 18 October.