Cullen Redwine Earp, Confederate cavalry officer, was born on August 8, 1828, in Marshall County, Alabama, son of William Earp and Betsy (Vaughn) Earp. He lived in Gilmer, Upshur County, Texas, and was a veteran of the Mexican War. He enlisted on May 6, 1847, in Huntsville, Alabama, in Company H of the Thirteenth U. S. Infantry and served until July 15, 1848. Earp was married to Harriet Emeline Dunkley of South Carolina in 1849. By 1860 he worked as a farmer on over 600 acres and owned three slaves. He enlisted as a first lieutenant in Company D of the Tenth Texas Cavalry on October 31, 1861, in Taos, Texas, and served under his brother Alex. The unit was mustered into service in October 1861 under the command of Matthew F. Locke of Gilmer.
In February 1862 the Tenth Texas Cavarly was ordered to join the Confederate Army in Corinth, Mississippi. They were forced to leave their horses before crossing the Mississippi River and thus became and remained a dismounted regiment for the remainder of the war. Earp was promoted to lieutenant colonel on May 8, 1862.
Earp participated in twenty-one engagements including Chickamauga, Atlanta, and Franklin. He led the unit in the battle of Richmond, Kentucky, in August 1862. Joining with the Ninth Texas Infantry, Fourteenth Texas Cavalry, and the Thirty-second Texas Cavalry in September 1862, the unit made up Ector's Brigade. In 1863 Ector's Brigade served with the Army of Tennessee under the command of Gen. Braxton Bragg. On November 7, 1863, the Tenth engaged in the battle of Chickamauga, Georgia, prompting the Clarksville Standard to report, "few, if any troops in the Confederate army have a more enviable fame than Ector's Brigade. It is composed of the 9th Regiment Texas Infantry, Col. Young, 10th, 14th, 15 (or 32) regiment Texas cavalry (dismounted) commanded respectively by Lieut. Col. Earp, Col. Camp and Col. Anderson…."
In October 1864 during the battle of Allatoona, Georgia, Earp was promoted to colonel in the place of William Hugh Young, who was taken prisoner and held as a POW in Ohio until the end of the war. Earp led the troops for the remainder of the battle. He was wounded in February 1865. The Tenth Texas Cavalry surrendered on May 4, 1865, in Citronelle, Alabama. Earp was paroled on July 3, 1865, and returned home to Gilmer, Upshur County. He died on October 16, 1865, as a result of sickness and his wounds. He was buried in his uniform with his gold watch in the Earp Cemetery near Gilmer. In 2008 the body of Colonel Earp was reinterred at the Hopewell Cemetery in Gilmer next to his brother Alex. He was reburied with full military honors by the Sons of the Confederacy, who fired Civil War-era muskets and cannons at the reburial.