History - Soviet Armenia
On May 28th , 1918 Russian Armenia was proclaimed independent republic. In September 1920 Turkey started the war against Armenia and occupied two thirds of its territory. In November the Red Army entered Armenia, and on November 29 th , 1920 the Armenian Soviet Socialist Republic was proclaimed.
On March 12th , 1922 Armenia, Azerbaijan and Georgia agreed on formation of the Federal Union of Socialist Soviet Republics of Transcaucasia which was transformed in the Transcaucasian Socialist Federal Soviet Republic on December 13th, 1922. Each republic preserved its independence. In 1936 TSFSR was abolished and Armenia along with Georgia and Azerbaijan were proclaimed independent union republics within the structure of the USSR.