Before the outbreak of the Civil War, Henry Hopkins Sibley enjoyed a long and varied career with the United States Military. It began after he graduated from the United States Military Academy in 1838. He fought during the Seminole Wars in Florida, the Mexican-American War, during frontier duty in Texas, and during the Utah War. It was during this military service that Sibley would come to invent items for the military which would share his name. One was the Sibley tent, which was briefly used by both sides during the Civil War. The other was the Sibley stove, which saw far more service and was used by the United States for many years after the war.
While service in New Mexico the Civil War broke out, Sibley resigned his commission from the United States army on May 13, 1861, and accepted an appointment to colonel in the Confederate army on May 16, 1861. By June 17, 1861, Sibley was promoted to brigadier general. His only major participation during the Civil War came during an attempt to invade New Mexico, and secure it for the Confederacy. He enjoyed initial success against Union forces under E.R.S. Canby, but was defeated at the battle of Glorietta Pass when his supply train was lost, and forced to retreat. He struggled throughout the rest of the war, receiving court martial charges and never again leading men in combat.