The Communist Party of Germany (German: Kommunistische Partei Deutschlands – KPD) was a major political party in Germany between 1918 and 1933, and a minor party in West Germany in the postwar period until it was banned in 1956. In the 1920s it was called the "Spartacists", since it was formed from the Spartacus League.

Founded in the aftermath of the First World War by socialists opposed to the war, led by Rosa Luxemburg, after her death the party became gradually ever more committed to Leninism and later Stalinism. During the Weimar Republic period, the KPD usually polled between 10 and 15 per cent of the vote and was represented in the Reichstag and in state parliaments. The party directed most of its attacks on the Social Democratic Party of Germany, which it considered its main opponent. Banned by the Nazi regime of Adolf Hitler, the KPD maintained an underground organization but suffered heavy losses. The party was revived in divided postwar West and East Germany and won seats in the first Bundestag (West German Parliament) elections in 1949, but its support collapsed following the establishment of a communist state in the Soviet occupation zone of Germany.

Walter Ulbricht (30 June 1893 – 1 August 1973) was a German communist politician. As First Secretary of the Socialist Unity Party from 1950 to 1971 (and then Honorary "Chairman" until his death), he played a leading role in the creation of the Weimar-era Communist Party of Germany (KPD) and later (spending the years of Nazi rule in exile in the Soviet Union) in the early development and establishment of the German Democratic Republic (East Germany). From President Wilhelm Pieck's death in 1960 he was the East German head of state until his own death in 1973.

Ulbricht was born in Leipzig, Saxony, where his father worked as a tailor. He spent eight years in primary school (Volksschule). After leaving school, he trained to be a joiner. Both his parents worked actively for the Social Democratic Party (SPD). Walter Ulbricht joined the party in 1912.

Ulbricht served in World War I from 1915 to 1917 in Galicia on the Eastern Front, and in the Balkans. He deserted in 1917, as he had opposed the war from the beginning. Imprisoned in Charleroi, in 1918 he was released during the German Revolution of 1918–1919. In 1917 he became a member of the Independent Social Democratic Party (USPD) after it split off from the Social Democratic Party (SPD) over support of Germany's participation in World War I. During the German Revolution he became a member of the soldier's soviet of his army corps and later a member of the KPD in 1920, joining its Central Committee in 1923. Ulbricht attended the International Lenin School of the Comintern in Moscow in 1924/1925. The electors subsequently voted him into the regional parliament of Saxony (Sächsischer Landtag) in 1926. He became a Member of the Reichstag for South Westphalia from 1928 to 1933 and served as KPD chairman in Berlin from 1929.

Friedrich Wilhelm Reinhold Pieck (German pronunciation: [ˈvɪlhɛlm ˈpiːk]; 3 January 1876 – 7 September 1960) was a German politician and a Communist. In 1949, he became the first President of the German Democratic Republic, an office abolished upon his death. He was succeeded by Walter Ulbricht, who served as Chairman of the Council of State.

Pieck was born the son of a coachman in the eastern part of Guben, Germany, which is now Gubin and part of Poland. While he initially trained to become a carpenter, a combination of world events, determined ideology, and political ambition led Pieck to a life of political activism.

As a carpenter, in 1894 Pieck joined the wood-workers' federation, which steered him towards joining the Social Democratic Party of Germany (SPD) the following year. Pieck became the chairman of the party urban district in 1899, and in 1906 became full-time secretary of the SPD. Although the majority of the SPD supported the German government in World War I, Pieck was a member of the party's left wing, which opposed the war. Pieck's openness in doing so led to his arrest and detention in a military prison. After being released, Pieck briefly lived in exile in Amsterdam. Upon his return to Berlin in 1918, Pieck joined the newly-founded Communist Party of Germany (KPD). In 1922, he became a founding member of the International Red Aid, serving first on the executive committee. In May 1925, he became the chairman of the Rote Hilfe.