In March 1990, Georgia declared sovereignty, unilaterally nullifying treaties concluded by the Soviet government since 1921 and thereby moving closer to independence. The Republic of Georgia boycotted the 17 March 1991 all-Union referendum on the renewal of the Soviet Union called by Gorbachev; however, 52.3% of Abkhazia's population (almost all of the ethnic non-Georgian population) took part in the referendum and voted by an overwhelming majority (98.6%) to preserve the Union. Most ethnic non-Georgians in Abkhazia later boycotted a 31 March referendum on Georgia's independence, which was supported by a huge majority of Georgia's population. Within weeks, Georgia declared independence on 9 April 1991, under former Soviet dissident Zviad Gamsakhurdia. Under Gamsakhurdia, the situation was relatively calm in Abkhazia and a power-sharing agreement was soon reached between the Abkhaz and Georgian factions, granting to the Abkhaz a certain over-representation in the local legislature.