The Germans also participated in the crushing of the Boxer Rebellion. Follpwing World War I, relations gradually improved as German military advisers assisted the Kuomintang nationalist government's National Revolutionary Army, though this would gradually change during the 1930s as Adolf Hitler allied himself with Japan. During the aftermath of World War II Germany and China were split in two states: a liberal democratic West Germany and the Republic of China on Taiwan allied with the Western Bloc while two communist states, East Germany and the People's Republic of China supported by the Eastern Bloc. The Cold War tensions led to Nationalist China and West Germany's alliance with the United States against communism and thus allied against Communist China with the Eastern part was allied through the Soviet Union.