The war resulted in the death of nearly ten million German soldiers and civilians; large territorial losses; the expulsion of about 15 million Germans from the former eastern territories and other countries; and the destruction of multiple major cities. The remaining national territory and Berlin were partitioned by the Allies into four military occupation zones.
The western sectors, controlled by France, the United Kingdom, and the United States, were merged on 23 May 1949, to form the Federal Republic of Germany (Bundesrepublik Deutschland, or BRD); on 7 October 1949, the Soviet Zone became the German Democratic Republic (Deutsche Demokratische Republik, or DDR). They were informally known as "West Germany" and "East Germany", and the two parts of Berlin as "West Berlin" and "East Berlin". East Germany selected East Berlin as its capital, while West Germany chose Bonn. However, West Germany declared the status of its capital Bonn as provisional,[26] in order to emphasise its stance that the two-state solution was an artificial status quo that was to be overcome one day.
West Germany, established as a federal parliamentary republic with a "social market economy", was allied with the United States, the UK and France. The country came to enjoy prolonged economic growth beginning in the early 1950s (Wirtschaftswunder). West Germany joined NATO in 1955 and was a founding member of the European Economic Community in 1957.
East Germany was an Eastern bloc state under political and military control by the USSR via the latter's occupation forces and the Warsaw Treaty. While claiming to be a democracy, political power was solely executed by leading members (Politburo) of the communist-controlled SED (Socialist Unity Party of Germany). Their power was ensured by the Stasi, a secret service of immense size, and a variety of SED suborganizations controlling every aspect of society. In return, the basic needs of the population were satisfied at low cost by the state. A Soviet-style command economy was set up; later, the GDR became a Comecon state. While East German propaganda was based on the benefits of the GDR's social programs and the alleged constant threat of a West German invasion, many of her citizens looked to the West for political freedoms and economic prosperity.[27] The Berlin Wall, built in 1961 to stop East Germans from escaping to West Germany, became a symbol of the Cold War.
Tensions between East and West Germany were somewhat reduced in the early 1970s by Chancellor Willy Brandt's Ostpolitik, which included the de facto acceptance of Germany's territorial losses in World War II.
In the summer of 1989, Hungary decided (May 2) to dismantle the Iron Curtain and open the borders (August 23), causing an exodus of thousands of East Germans (September 11) going to West Germany via Hungary. The effects of the Hungarian events had devastating effects on the GDR, with mass demonstrations. The East German authorities unexpectedly eased the border restrictions in November, allowing East German citizens to travel to the West. Originally intended as a pressure valve to retain East Germany as a state, the opening of the border actually led to an acceleration of the Wende reform process in East Germany, which finally concluded with the Two Plus Four Treaty a year later on 12 September 1990, under which the four occupying powers renounced their rights under the Instrument of Surrender, and Germany regained full sovereignty. This permitted German reunification on 3 October 1990, with the accession of the five re-established East German states (New Länder or "new federal states").
