1st U.S. Cavalry
1st U.S. Cavalry Regiment (1855-1861) - The 1st U.S. Cavalry Regiment was established by Congress in March 1855. The Regiment (along with the 2nd U.S. Cavalry also established in 1855) were, called the "Jeff Davis Regiments" as they were the brainchild of Secretary of War Jefferson Davis. The 1st U.S. Cavalry was organized and trained at Fort Leavenworth and the 2nd U.S. Cavalry was organized at Jefferson Barracks and deployed to the Texas frontier.
In 1861 the mounted services were reorganized as follows:
- 1st U.S. Cavalry was redesignated the 4th U.S. Cavalry
- 1st U.S. Dragoons was redesignated the 1st U.S. Cavalry
- 2nd U.S Dragoons was redesignated the 2nd U.S. Cavalry
- Regiment of Mounted Rifles was redesignated the 3rd U.S. Cavalry
- 2nd U.S. Cavalry was redesignated the 5th U.S. Cavalry.