Why was Berlin divided into four occupation sectors after World War II?

Following the unconditional surrender of Nazi Germany in 1945, the victorious Allied powers—the United States, the United Kingdom, France, and the Soviet Union—divided Germany into four occupation zones to administer the defeated nation.12

Although Berlin was located deep within the Soviet-controlled zone, the city was placed under joint four-power authority. This arrangement was based on agreements reached in London in 1944 and confirmed at the Potsdam Conference in 1945. To facilitate administration, the city was partitioned into four sectors, with each of the Allies controlling one.2341

This division was intended to be an administrative measure for the governance of the former capital. However, as ideological differences between the Western Allies and the Soviet Union intensified, the sectors became focal points of the Cold War, eventually leading to the city's formal split into East Berlin and West Berlin and the construction of the Berlin Wall.23154