Established in 1863, the SPD is by far the oldest existing political party represented in the Bundestag and was one of the first Marxist-influenced parties in the world. From the 1890s through the early 20th century, the SPD was Europe's largest Marxist party and was consistently the most popular party in Germany. During the First World War, the party split between a pro-war mainstream and the anti-war Independent Social Democratic Party, of which some members went on to form the Communist Party of Germany (KPD). The SPD played a leading role in the German Revolution of 1918–1919 and was chiefly responsible for the foundation of the Weimar Republic. SPD politician Friedrich Ebert served as the first President of Germany and the SPD was the strongest party until 1932. After the rise of the Nazi Party to power it was the only party in the Reichstag to vote against the Enabling Act of 1933 that gave Hitler dictatorial powers. The SPD was subsequently banned in 1933 together with all parties other than the NSDAP. Subsequently the SPD operated in exile as the Sopade.