Azerbaijan Soviet Socialist Republic
The Azerbaijan Soviet Socialist Republic, also referred to as the Azerbaijani Soviet Socialist Republic, Azerbaijan SSR, Azerbaijani SSR, AzSSR, Soviet Azerbaijan or simply Azerbaijan, was one of the constituent republics of the Soviet Union between 1922 and 1991. Azerbaijan SSR was created on 28 April 1920 following the Red Army invasion of Azerbaijan.
Source: Wikipedia — Azerbaijan Soviet Socialist Republic (CC BY-SA 4.0)