In 1783 the last Tatar state, Crimea, was annexed to Russia. The Nogais were gradually pushed eastward into the Caucasus by the Russian settlers. The Crimean Tatars themselves—except for the large numbers that emigrated to Turkey at the time of the Russian conquest of Crimea and after the Crimean War—remained in the Crimea until World War II and formed the basis of the Crimean Autonomous SSR, founded in 1921. It was dissolved in 1945, and all Crimean Tatars (about 200,000 in 1939) were exiled to Uzbekistan and Kazakhstan for alleged collaboration with the Germans. In 1956 they regained civil rights and since the late 1980s many have returned to Crimea; their numbers there now exceed prewar levels. Following the disintegration of the USSR, leaders of Tatarstan began to press the Russian government for increased powers. In a 1992 referendum, over 61% of the voters supported a "sovereign" Tatarstan.