The movement's roots lay in the anti-conscription violence of 1916 that erupted when the Russian Empire began to draft Muslims for army service during World War I. In the months following the October 1917 Revolution the Bolsheviks seized power in many parts of the Russian Empire and the Russian Civil War began. Turkestani Muslim political movements attempted to form an autonomous government in the city of Kokand, in the Ferghana Valley. The Bolsheviks launched an assault on Kokand in February 1918 and carried out a general massacre of up to 25,000 people. The massacre rallied support to the Basmachi movements who waged a guerrilla war and a conventional war that seized control of large parts of the Ferghana Valley and much of Turkestan.