The Majority Social Democratic Party of Germany (German: Mehrheitssozialdemokratische Partei Deutschlands, MSPD) was the name officially used by the Social Democratic Party of Germany (SPD) between April 1917 and September 1922.[1] The name differentiated it from the Independent Social Democratic Party (Unabhängige Sozialdemokratische Partei Deutschlands, USPD), which split from the SPD as a result of the party majority's support of the government during the First World War.
Governments led by the MSPD steered Germany through the German Revolution of 1918–1919 and the first years of the Weimar Republic. They followed a moderate course towards a parliamentary system and often used military force against the radical left groups that wanted a soviet style government. The MSPD introduced important social reforms such as the eight-hour workday and early forms of unemployment and health insurance. The party won more votes than any other in the first two national elections.
The breakaway USPD was considerably weakened after the Spartacus League, its revolutionary wing, joined with other communist groups to form the Communist Party of Germany in January 1919. In 1922 the majority of the remaining USPD members united with the MSPD, and the party returned to its original SPD name.