Peter F. Ross, Texas Ranger, cattleman, and Confederate Army officer, was born on July 27, 1836, at Bentonsport, Missouri, the son of Catherine H. (Fulkerson) and Shapley Prince Ross. In 1838 he moved with his family to Milam County, Texas. After attending Mount Vernon Military Academy in New York from 1853 to 1855 he returned to Texas, where he assisted his father, a Texas Indian agent, in his duties on the frontier. Peter was described as "a tall, wiry, youth, physically and mentally well fitted" for a military career. In 1858 he was commissioned captain in the Texas Rangers and raised and commanded a company that served for two years against the Comanches and other warlike tribes on the northwest frontier. In May 1860 he served as captain of the "spy company" of allied Indians that accompanied Col. Middleton Tate Johnson's expedition against the Comanches and pushed into Indian Territory without encountering the enemy. With the outbreak of the Civil War he raised a company of cavalry in Dallas for Confederate service that was organized as Company G of Col. B. Warren Stone's Sixth Texas Cavalry regiment. Ross was elected captain of his company but was soon elevated to regimental major. He served under Col. Stone until his brother, Gen. Lawrence Sullivan "Sul" Ross became regimental commander in May 1862, At the battle of Corinth, Mississippi, in 1862, he received two serious wounds. He was promoted to colonel of the Sixth Texas Cavalry Regiment in 1863 and he commanded that regiment during John Bell Hood's North Georgia and Tennessee campaigns.
After the war, as a cattleman, Ross made several trail drives to New Orleans. He married Laura Harrison, the daughter of Gen. James E. Harrison, on December 26, 1866; they had two children. In 1870 Ross moved to Los Angeles, California, where he farmed and engaged in trade. He returned to Texas in 1874 and served as deputy sheriff of McLennan County under his brother Sul until elected sheriff himself in 1875. After serving two terms as sheriff Ross bought a farm in 1880 on the Brazos River some ten miles below Waco. He died on March 26, 1909, and was buried in Waco. He was a Democrat, a Knight Templar, and a Baptist.