The Col. George Henry Sweet's 15th Texas Cavalry was organized initially at San Antonio Texas in the fall of 1861 and recruited troops as it was moved through Texas to to Little Rock. In January 1862, the regiment was reorganized at Little Rock and was moved to Camp Nelson 2-miles east of Cabot Arkansas. In October the regiment was briefly placed in the 4th Brigade of Maj.Gen. John G. Walker's Texas Division. In the fall of 1862, the 15th Texas Cavalry was detached from Walker's Division and later surrendered at Arkansas Post on January 11, 1863. Col. Sweet was exchanged and he returned to Arkansas where he attempted to reorganize the 15th Texas Dismounted Cavalry with all the prisoner of war escapees he could locate. Col. Sweet took the position of commandant of Camp Ford prisoner of war camp and what was left of the 15th Dismounted Cavalry was sent east of the Mississippi River and combined with other regiments in Ector's Brigade.
A measles and camp fever (typhoid) epidemic in Arkansas spread through the ranks in the spring of 1862. Many soldiers died and were buried in the woods near Camp Nelson with wooden markers. Before moving to Camp Nelson, many soldiers were also buried in the National Cemetery at Little Rock.
In 1895, the United Confederate Veterans moved the remains of the soldiers in the woods to the Camp Nelson Cemetery and installed a single granite monument. The original wooden markers had deteriorated and the individual soldiers graves could not be identified. The soldiers were first buried in a location that was hidden from the camp in order to preserve the moral of the troops. That was a common practice during the war.
The Col. Joseph Warren Speight's 15th Texas Infantry was raised in Waco and McClennan County and is a completely different regiment.