The American and British occupation zones in Germany, after World War II, merge to form the Bizone, which later (with the French zone) became part of West Germany.
The Bizone (German: [ˈbiːˌt͡soːnə] (listen)) or Bizonia was the combination of the American and the British occupation zones on 1 January 1947 during the occupation of Germany after World War II. With the addition of the French occupation zone on 1 August 1948 the entity became the Trizone (German: [ˈtʁiːˌt͡soːnə] (listen); sometimes jokingly called Trizonesia (German: Trizonesien, German pronunciation: [tʁit͡soˈneːzi̯ən] (listen))). Later, on 23 May 1949, the Trizone became the Federal Republic of Germany, commonly known as West Germany.