The Berlin Wall was a guarded concrete barrier that encircled West Berlin of the Federal Republic of Germany from 1961 to 1989, separating it from East Berlin and the German Democratic Republic. Construction of the Berlin Wall was commenced by the government of the GDR on 13 August 1961. It included guard towers placed along large concrete walls, accompanied by a wide area that contained anti-vehicle trenches, beds of nails and other defenses. The primary intention for the Wall's construction was to prevent East German citizens from fleeing to the West.

West Berlin was a political enclave which comprised the western part of Berlin from 1948 until 1990, during the Cold War. Although West Berlin lacked any sovereignty and was under military occupation until German reunification in 1990, the territory was claimed by the Federal Republic of Germany (FRG), despite being entirely surrounded by East Germany (GDR). The legality of this claim was contested by the Soviet Union and other Eastern Bloc countries. However, West Berlin de facto aligned itself politically with the FRG from May 1949 and was thereafter treated as a de facto city-state of that country. After 1949, it was directly or indirectly represented in the institutions of the FRG, and most of its residents were citizens of the FRG.