Sozialdemokratische Partei Deutschlands
Germanys' oldest political party, formed in 1875, the Sozialdemokratische Partei Deutschlands (SPD) (Social Democratic Party of Germany), identifies with workers and trade unions. Its ideology is socialist with Marxist influences.
While the immediate postwar Weimar Chancellors were of the party, and it remained the strongest single party until 1932, it was in opposition during most of the Weimar Republic. The KPD Communists on its left, and the conservatives and Nazis strongly opposed it. It had difficulty forming coalitions with the center-right. As opposed to the monarchism and authoritarianism of some other parties, it always supported a democratic model.