Exclaves of West Berlin in East Germany

During the Division of Germany (1945–90), West Berlin was controlled by the Western Allies (United States, United Kingdom, France), but was completely surrounded by the territory of East Germany and East Berlin. Twelve small areas of land belonging to West Berlin were not connected by land to the rest of West Berlin, but were exclaves surrounded by the East German territory. There was also Tiefwerder, an inhabited East German exclave,

When Greater Berlin was constituted on 1 October 1920, a total of ten Berlin exclaves were created surrounded by the Province of Brandenburg. Although these exclaves were under Berlin’s administration, they were not connected by land to the city proper (as is the definition of exclave). The signed on 12 September 1944 set out Allied arrangements for dividing Germany into zones of occupation and Berlin into sector of occupation after the war. The protocol took the old German administrative borders as its guide. As it happened, all of the exclaves belonged to West Berlin boroughs. As a result, they ended up being retained as enclaves after 1945, first inside the Soviet occupation zone and after 1949 inside East Germany.

During the Cold War these exclaves raised sovereignty issues that led to repeated conflicts. Traffic to and from Steinstücken, for instance, the only exclave with permanent residents, was often hindered as it crossed East German territory, resulting in frequent confrontations between East German authorities, residents, representatives of the Berlin Senate and the U.S. Army.

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