The Socialist Soviet Republic of Abkhazia (SSR Abkhazia) had been established in 1921 after the Red Army invaded Georgia. The SSR Abkhazia, which was united with the Georgian SSR later that year as a "treaty republic," existed until 1931. During this time it was granted considerable amounts of autonomy, by virtue of its unique status in relation to Georgia. However this concerned the Soviet and Georgian authorities, and it was reduced to that of other autonomous republics. So on 19 February 1931 the SSR Abkhazia was reformed as the Abkhaz Autonomous Soviet Socialist Republic, wholly under the control of Georgia, which itself was a constituent republic of the Transcaucasian Socialist Federative Soviet Republic (TSFSR).