In 1989, independence activists formed a mass movement called the Estonian Citizens' Committees () and started registering persons who were Estonian citizens by birth according to the "jus sanguinis" principle, i.e., persons who held Estonian citizenship in June 1940 (at which point Estonia's de facto structures of state were systematically dismantled and reorganized, after the country had been occupied by the Soviet Union), and their descendants. People who did not satisfy these criteria were invited to file applications for citizenship. By February 1990, 790,000 citizens and about 60,000 applicants had been registered.