The Department of the Gulf was a military administrative region established by the United States during the American Civil War. It was created in 1862 to oversee Union operations in the Gulf of Mexico and surrounding areas, particularly focusing on the states of Louisiana, Mississippi, and Texas. The department played a crucial role in coordinating military efforts and maintaining control over key ports and waterways. Under the command of Major General Benjamin Butler, the department implemented various strategies to suppress Confederate forces and support the Union cause. The department's actions included military campaigns, occupation of cities, and efforts to secure supply lines, significantly impacting the war's progress in the region.