The 5th Cavalry Regiment is a historical unit of the United States Army that began its service on August 3, 1861, when an act of Congress enacted "that the two regiments of dragoons, the regiment of mounted riflemen, and the two regiments of cavalry shall hereafter be known and recognized, as the first, second, third, fourth, and fifth regiments of cavalry respectively..." and continues in modified organizational format in the U.S. Army.

Albert Sidney Johnston was an American military officer who served as a general in three different armies: the Texian Army, the United States Army, and the Confederate States Army. He saw extensive combat during his 34-year military career, fighting actions in the Black Hawk War, the Texas-Indian Wars, the Mexican–American War, the Utah War, and the American Civil War.