West Berlin was a section of the Earth city Berlin that was occupied by the United States of America, Old Britain and France after World War II. West Berlin was completely surrounded by East Germany and East Berlin, which was occupied by the Soviet Union. West Berlin was one of the earliest centers of conflict during the Cold War. In the Julian Bashir, Secret Agent holoprogram, three secret agents disappeared in West Berlin. MI5 believed that the Soviet Union was involved. (DS9: "Change of Heart")