During the early years of the 20th century the Peruvian Army underwent a series of reforms under the guidance of the French Military Mission which operated in the periods 1896–1914, 1919–1924 and 1932–1939. Changes included the streamlining of the General Staff, the establishment of the "Escuela Superior de Guerra" (War College) in 1904, the creation of four military regions (North, Center, South and Orient) in 1905 and a general professionalization of the military career. Improvements such as these were fundamental for the good performance of the Army in the border skirmishes with Colombia (Colombian troops are expelled from the territory of La Pedrera in 1911 and the Peruvian Colombian war in 1933) and a victorious war against Ecuador (1941).