The Congress of Estonia (Estonian: Eesti Kongress) was an innovative grassroots parliament established in Estonia in 1990–1992 as a part of the process of regaining of independence from the Soviet Union. It also challenged the power and authority of the pre-existing quasi-parliament in the country, called the Supreme Soviet of the Estonian SSR, which had been imposed on Estonia after the Soviet invasion, occupation and illegal annexation of Estonia in 1940. The Congress of Estonia declared that it represented the highest authority on questions of Estonian statehood and citizenship, deriving this authority from the consent and initiative of the citizens of Estonia. The aim of the Congress was to restore Estonian independence based on the principle of legal continuity, with the pre-1940 Republic of Estonia, which had been established in 1918, as the foundation. Activity 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. In February 1990, the election of a body of representatives of these citizens – the Congress of Estonia – was conducted by those who had been registered. The Congress had 499 delegates from 31 political parties. The Estonian National Independence Party (, usually abbreviated as ERSP) won the most seats. Other parties represented included the Popular Front of Estonia, the Estonian Heritage Society and the Communist Party of Estonia. The permanent standing committee of the Congress of Estonia – the Committee of Estonia () – was chaired by Mr. Tunne Kelam. In September 1991, a Constituent Assembly was formed of equal numbers of members of the Supreme Soviet and the Congress of Estonia to work out a new Constitution for the Republic. The new constitution was approved by referendum in June 1992, using the constitution replacement process specified in the 1938 constitution as a matter of legal continuity of the Republic of Estonia. Both the Congress of Estonia and the Supreme Soviet dissolved themselves in October 1992, with the swearing-in of the first