Grotewohl chaired the Council of Ministers after the establishment of the GDR in 1949 and served as the de jure head of government under First Secretary Walter Ulbricht until his death in 1964.

Grotewohl was brutally beaten, arrested and imprisoned several times by Nazi police and subsequently forced to leave Braunschweig, first moving to Hamburg then from 1938 to Berlin, where he worked as a greengrocer and industrial representative.

[6] According to Heinz Voßke's 1979 biography of Grotewohl, this lifestyle allowed him to avoid being conscripted into the Volkssturm during the closing months of World War II.

Immediately after the war, the Soviets believed the Communist Party of Germany (KPD), rebuilt by the "Ulbricht Group" and led by Wilhelm Pieck, would naturally develop into the strongest political force in their zone with some guidance.

Unification was pushed by some members of Grotewohl's SPD in the Soviet zone and Berlin, under the belief that division between the main left-wing parties had led to Nazi rise to power.

In April 1946, the KPD and the eastern branch of the SPD merged as the Socialist Unity Party (SED), with Pieck and Grotewohl serving as co-chairmen.

The few recalcitrant SPD supporters were condemned as "Agents of Schumacher" and shunted aside, accelerating a process that left the SED as essentially the KPD under a new name.

On 12 October 1949, Grotewohl became the first prime minister (Ministerpräsident) of the German Democratic Republic (commonly known as East Germany or the GDR), five days after its establishment from the Soviet Occupation Zone with the SED as the ruling party.

Grotewohl was appointed Chairman of the Council of Ministers (Ministerrat), the de jure government of the GDR, while Pieck served as State President.

However, the Council of Ministers, despite being officially defined as the "government" of East Germany, was reduced to a transmission belt for policies made by the SED's Politburo.

However, Grotewohl was not only examined by specialist physicians in the GDR, who identified arteriosclerosis and incipient calcification of the coronary system in his heart in 1953, but also took advantage of the medical care of top Soviet politicians in Moscow.

[7] On 4 April 1960, Grotewohl traveled to a four-week relaxing holiday on the Black Sea; eight months later, he arrived again for several weeks in the Soviet sanatorium in Barvikha.

[7] At the end of October 1960, Grotewohl had commissioned his top deputy, Willi Stoph, as acting prime minister, although he officially remained in office.

The permanent cardiovascular disorders prevented Grotewohl's return to politics, and he was no longer able to participate actively in the meetings of the leadership committees of the party and the government.

On the contrary, in September 1960 Grotewohl became Deputy Chairman of the State Council, the collective body that was created on the base of the Presidency which was abolished after Wilhelm Pieck's death in 1960.

[9] Hans Grotewohl (1924–1999), was an architect who was sent by his father to lead a German Work Team for rebuilding Hamhung, North Korea, in 1954 after the Korean War.