Arkansas had seceded from the Union in April 1861 and joined the Confederate States of America, raising during the war a total of 48 infantry regiments, more than 30 cavalry regiments and another 25 cavalry battalions, and about 22 artillery batteries for the Confederate Army. Once Union forces had entered the state, however, pro-Union citizens (both black and white) volunteered for the Union Army to serve in 11 infantry regiments, 6 cavalry regiments and 2 artillery batteries.