Background: Part of Romania during the interwar period, Moldova was incorporated into the Soviet Union at the close of World War II. Although independent from the USSR since 1991, Russian forces have remained on Moldovan territory east of the Dniester River supporting the Slavic majority population, mostly Ukrainians and Russians, who have proclaimed a "Transnistria" republic. One of the poorest nations in Europe, Moldova became the first former Soviet state to elect a Communist as its president in 2001.