Trans-Mississippi Department

The Trans-Mississippi Department was a militarily administrated subdivision of the Confederate States of America west of the Mississippi, comprising Texas, Arkansas, Missouri, Indian Territory, and parts of Arizona and Louisiana.

The department was formed May 26, 1862, comprising Missouri, Arkansas, Texas, Indian Territory (now Oklahoma), Confederate Arizona (which included parts of New Mexico), and the part of Louisiana west of the Mississippi River. When created, it absorbed the previously established Trans-Mississippi District (Confederate Department Number Two), which had been organized January 10, 1862, to include the Indian Territory, Missouri, Arkansas (except for the country east of St. Francis County, Arkansas to Scott County, Missouri), and that part of Louisiana north of the Red River. The combined department had its headquarters at Shreveport, Louisiana, and Marshall, Texas. It was responsible for the Confederate theater of operations west of the Mississippi. Its forces were sometimes referred to as the "Army of the Southwest."

Because the department was commanded often during its existence by General Edmund Kirby Smith, it became popularly known as "Kirby-Smithdom."

Department Two's commander:

The combined department's commanders included:

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