The Social Democratic Party of Lithuania (LSDP) is a social democratic political party in Lithuania, founded in 1896 as an underground Marxist group in opposition to the Russian Empire. The party was oppressed under both the Lithuanian dictatorship from 1926 to 1940 and under the Soviet Union from 1940 to 1989. The LSDP led a minority government from 2004 to 2008, and it became one of the major parties in the country. In 2016, it held 38/141 Seima seats, 2/11 European Parliament seats, 371/1,524 municipal council seats, and 8/15 cabinet seats.