History of Germany (1945–1990)

The history of Germany from 1945 to 1990 encompasses the period following World War II. The period began with the Berlin Declaration, marking the abolition of the German Reich and Allied-occupied period in Germany on 5 June 1945, and ended with the German reunification on 3 October 1990.

Following the collapse of the Third Reich in 1945 and its defeat in World War II, Germany was stripped of its territorial gains. Beyond that, more than a quarter of its old pre-war territory was annexed by communist Poland and the Soviet Union. The German populations of these areas were expelled to the west. Saarland was a French protectorate from 1947 to 1956 without the recognition of the "Four Powers", because the Soviet Union opposed it, making it a disputed territory.

At the end of World War II, there were some eight million foreign displaced people in Germany, mainly forced laborers and prisoners. This included around 400,000 survivors of the Nazi concentration camp system, where many times more had died from starvation, harsh conditions, murder, or being worked to death. Between 1944 and 1950, some 12 to 14 million German-speaking refugees and expellees arrived in Western and central Germany from the former eastern territories and other countries in Eastern Europe; an estimated two million of them died on the way there. Some nine million Germans were prisoners of war.

With the beginning of the Cold War, the remaining territory of Germany was divided between the Western Bloc led by the United States, and the Eastern Bloc led by the USSR. Two separate German countries emerged:

• the Federal Republic of Germany, established on 23 May 1949, commonly known as West Germany, was a parliamentary democracy with an ordoliberal economic system and free churches and labor unions;
• the German Democratic Republic, established on 7 October 1949, commonly known as East Germany, was a Marxist–Leninist socialist republic with its leadership dominated by the Soviet-aligned Socialist Unity Party of Germany (SED).

Under Chancellor Konrad Adenauer, West Germany built strong relationships with France, the United Kingdom, the United States, and Israel. West Germany also joined the North Atlantic Treaty Organization and the European Economic Community. East Germany's economy, centrally planned in the Soviet style, grew increasingly stagnant; the East German secret police tightly controlled daily life, and the Berlin Wall (1961) ended the steady flow of refugees to the West. The country was reunited on 3 October 1990, following the decline and fall of the SED as the ruling party of East Germany and the Peaceful Revolution there.