French expeditions and colonization into the Middle Niger region by the French gained steam in the 1880s. Bamako was established as a French colonial post in 1883. A series of military expeditions led to French imperial control over the
Imamate of Futa Jallon and treaties with other groups by the 1890s. A decree of 2 March 1907 added the
cercles of
Fada N'gourma and
Say, which had been part of the colony of
French Dahomey (present-day
Benin). On 1 January 1912, the military territory of Niger was split off from Upper Senegal and Niger, and was erected into a
colony in 1922. Between November 1915 and February 1917, the Colony of Upper Senegal and Niger witnessed vastly popular, temporarily successful, and sustained armed opposition to the colonial government in its western Volta region, which is referred to as the
Volta-Bani War. It challenged colonial government authority for more than a year in an area stretching from
Koudougou (in present-day
Burkina Faso) in the east, to the banks of the
Bani River (present-day
Mali) in the west. This was the most significant armed opposition to colonial authority organized anywhere in sub-Saharan Africa in the period preceding World War II.
Division After
World War I ended, the unsuspected success of this resistance movement caused the French authorities to issue the decree "Concerning the Division of the Colony of Upper Senegal and Niger and the Creation of the Colony of Upper Volta" of 1 March 1919, which divided the colony into two distinct units: •
French Upper Volta, formed from the
cercles of
Gaoua,
Bobo-Dioulasso,
Dédougou,
Ouagadougou,
Dori, Say, and Fada N'Gourma; • the remaining territory – present-day
Mali – was still called "Upper Senegal and Niger" until it was renamed "
French Sudan" on 1 January 1921, implementing the decree of 4 December 1920, "For the Denomination of the Colonies and Territories Composing the General Government of French West Africa." ==Geography==