The Military Governor for the United States Zone (1945–1949) and the United States High Commissioner for Germany (HICOG) (1949–1952) had their headquarters in the IG Farben Building, intentionally left undamaged by the Allies' wartime bombardment. The heavily destroyed city decided in the spirit of the time to plan a major reconstruction of the historical city center, retaining the old road system. The formerly independent city republic joined the state of Hesse in 1946. As the state capital was already at the smaller city of Wiesbaden and the American armed forces had used Frankfurt as their European headquarters, the city seemed most promising candidate for the West German federal capital. The American forces even agreed to withdraw from Frankfurt to make it suitable, as the British forces already had withdrawn from Bonn. Much to the disappointment of many in Frankfurt, however, the vote narrowly favored Bonn twice. Despite this, the mayor looked towards the future, seeing that with the division of Germany and relative isolation of Berlin, Frankfurt could take over positions in trade and commerce previously filled by Berlin and Leipzig. Since Bonn never played an important role despite its status as capital, Frankfurt, Hamburg, and Munich realigned themselves, passing from regional centers to international metropolises and effectively forming three West German cultural and financial capitals.