After a brief period of independence between the two World Wars, Latvia was annexed by the USSR in 1940. It reestablished its independence in 1991 following the breakup of the Soviet Union. Although the last Russian troops left in 1994, the status of the Russian minority (some 30% of the population) remains of concern to Moscow. Latvia joined both NATO and the EU in the spring of 2004.
Sources: CIA World Factbook, November 2004