Indian Territory in the American Civil War

During the American Civil War, Indian Territory occupied most of what is now the U.S. state of Oklahoma. It served as an unorganized region set aside for Native American tribes of the Southeastern United States following the Indian Removal Act. It was occupied by captured Native Americans who had been removed from their lands. The area was the scene of numerous skirmishes and seven officially recognized battles involving Native American units allied with the Confederate States of America, Native Americans loyal to the United States government, and Union and Confederate troops.

A total of 7,860 Native Americans participated in the Confederate Army, as both officers and enlisted men; they were mostly from the Five Civilized Tribes: the Cherokee, Chickasaw, Choctaw, Creek, and Seminole nations. The Union organized several regiments of Indian Home Guard to serve in the Indian Territory and sometimes adjacent areas of Kansas, Missouri, and Arkansas.

After abandoning its Indian Territory forts early in the Civil War, the Union army was unprepared for the logistical challenges of trying to regain control of the territory from the Confederate government. The area was largely undeveloped, railroads did not exist in this area and the Union did not have enough troops to control the few roads. Pro-Union Indians had abandoned their own farms because of raids by pro-Confederacy Indians and fled to Kansas or Missouri, seeking protection by Union army forces there. It was not feasible to sustain a large military operation by living off the land. This was demonstrated in 1862, when General William Weer led 5,000 men in the "Indian Expedition" into Indian Territory from Baxter Springs, Kansas. Weer's troops captured a Confederate supply train at the Battle of Locust Grove. However, no Union supplies arrived after that, and the expedition ran short of food, ammunition and other essentials. Weer's men mutinied, arresting Weer and putting Colonel Frederick Salomon in command.

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