According to a 2003 United Nations High Commissioner for Refugees report , unidentified local authorities expelled Azeris in response to anti-Armenian pogroms in Sumgait and Baku of 1988-89 . Armenians reached 98 % of the national population . Armenian nationalists , together with the Soviet republic 's administration , were thought to have co-operated in driving Azeris out . The remainder of the Azerbaijani population was driven away from country in 1991 . By 2004 , Armenia was the only country of the former USSR with a homogeneous population ( 97,9 % Armenians ) and not more than 30 Azerbaijanis were living in Armenia
Sumgait
Sumgait pogrom
Deportation of Azerbaijanis from Armenia