The Confederate Trans-Mississippi Department was formed May 26, 1862 to include Missouri, Arkansas, Texas, Indian Territory, and Louisiana west of the Mississippi River. It absorbed the Trans-Mississippi District (Department Number Two), which had been organized January 10, 1862, to include that part of Louisiana north of the Red River, the Indian Territory, and the states of Missouri and Arkansas, except for the country east of St. Francis County, Arkansas, to Scott County, Missouri. The combined department had its headquarters at Shreveport, Louisiana & Marshall,Texas.