Henry Petty Cayce, a Texas soldier through five wars and thirty years, was born at Franklin, Williamson County, Tennessee, on September 5, 1819, to Thomas Dodson and Hannah (Stanley) Cayce. The family came to Texas in December 1829, and Thomas Cayce received a league of land on the Colorado River, just below the present Wharton-Matagorda county line. Where the road from Columbia to Goliad crossed the river he built a ferry that became known as Cayce's Ferry. In the fall of 1835, just a few days after his sixteenth birthday, Henry Cayce, under the command of Captain Goodwin and Philip Dimmitt, rode to Goliad to capture La Bahía from the Mexicans. Early in November 1835 Dimmitt sent Cayce on special duty, under Capt. Bailey Hardeman, to move an eighteen-pound cannon from Dimitt's Landing, at the mouth of the Lavaca River, to San Antonio for use in the siege of Bexar. Twenty men from the Bay Prairie area started on the trip. They were joined along the way by others, including twenty members of the Mobile Grays, until they numbered seventy-five. They pushed and pulled the cannon for almost 200 miles and made it to San Antonio two days after the Mexicans surrendered. Some say they surrendered because Gen. Martín Perfecto de Cos knew the cannon was coming. Cayce went back to Goliad and was discharged on January 14, 1836, when Dimmitt and the Bay Prairie men were sent home. He received a bounty grant of 320 acres for this service.
Cayce returned to Goliad with some of the men that were marching to join James W. Fannin, Jr. He was still at Goliad when Fannin started the retreat to Victoria and was sent a few miles ahead of the main body of troops to guard some wagons. When Fannin and his men were surrounded, Cayce and the others with the wagons eluded the enemy and escaped. Cayce made his way to the Colorado River and found Sam Houston and the Texas army. Houston believed the sixteen-year-old-boy was too young to fight another battle, and he sent him to guard the women and children in the Runaway Scrape. This caused him to miss the battle of San Jacinto, and he always regretted it.
After the war Cayce's father sent him back to Tennessee to finish his education. He studied law and returned to Texas four years later. He came home just in time to learn of the death of his brother, George Washington Cayce, who was killed by Comanches at the Council House Fight in San Antonio. In March of 1842 he joined Albert Clinton Horton after the invasion of Rafael Vásquez. In September he joined Colonel Horton again when Gen. Adrián Woll and a thousand Mexican troops captured San Antonio.
Cayce married Mary Francis Slade on November 29, 1842, in Matagorda County, and subsequently started buying land in Wharton County. He became a prosperous farmer with extensive holdings. He owned many slaves but was a kindhearted man and never sold any of them.
In 1846 he served with Gen. Zachary Taylor in the Mexican War and fought at Matamoros. He was elected county commissioner of Wharton County in 1848 and served until 1852. In 1861 he joined the Confederate Army and was commissioned a lieutenant in Col. Joseph Bates's Fourth Texas Volunteer regiment. On October 22, 1861, Cayce placed an advertisement in the Columbia Democrat and Planter asking for volunteers to join the "Flying Artillery." One of the first to answer the call was his sixteen-year-old son, Henry P. Cayce, Jr. Father and son rode off to fight this war together. Henry Cayce spent four years using the big guns of his artillery battery to keep the Yankees from invading the Texas coast. By 1865 he was a lieutenant colonel and was sent to Louisiana to stop the Union forces from overrunning Texas from the east.
After the war he returned again to Wharton County. His slaves were gone, the land was overgrown, and he had no money. He practiced law in Wharton for a few years, but the problems of Reconstruction were too much, and he decided to move on and start over again. In the winter of 1873 he set out for Coryell County with his wife, most of their nine children, and many members of both of their families. Many illnesses and some deaths occurred on the long, cold trip. The caravan stopped in Milam County to rest and to let Cayce practice law for a while because they needed the money. But without recovering from the cold and exposure of the trip he died, on November 26, 1875, and was buried at Davilla in Milam County.