Which Soviet republic was the first to declare independence?

Baltic states, incorporated into the Soviet Union in 1940, strongly pushed towards independence. First the lead was taken by Latvia with large demonstrations in 1986 and 1987, but Estonia and Lithuania soon joined the movement. On March 11, 1990 the newly elected parliament of the Lithuanian SSR, elected Vytautas Landsbergis to the position of Chairman of the Supreme Council. Vytautas Landsbergis promptly declared the restoration of Lithuanian independence.