James Buchanan Gillett, Texas Ranger, author, and rancher, was born in Austin on November 4, 1856, the son of James S. and Elizabeth (Harper) Gillett. He had two sisters. The children were sent to private schools since there were no public schools in Austin at that time. Jim found them irksome, and in 1868 he quit school for a life in the outdoors. Because of his mother's ill health, the family moved to Lampasas in 1872. This was cattle country, and in 1873 he left home to work for nearby cattlemen. After his father's death in April 1874, he left for Menardville (later Menard). There, on June 1, 1875, Gillett joined the Texas Rangers, Daniel Webster Roberts's Company D, Frontier Battalion. He spent six years with the rangers on the frontier, including service with companies A, E, and C. This was the bloodiest period of the Texas Indian wars. Gillett fought Kiowa, Comanche, and Lipan Apache indians, as well as cattle thieves and outlaws. He was stationed in El Paso County in 1881, when, accompanied by ranger George Lloyd, he went to Zaragoza, Chihuahua, without extradition papers to capture Eunofrio Baca, who had murdered the newspaper editor A. M. Conklin in Socorro, New Mexico. Gillett grabbed the killer and galloped to the Rio Grande, four miles away, with men from the town chasing and shooting at them. Though Gillett turned Baca over to the sheriff in Socorro, Baca was lynched by a mob. There were international rumblings, and the Mexican government sent a complaint to Washington, but after a short time the furor diminished.
On February 10, 1881, Gillett married Helen Baylor, daughter of Capt. George W. Baylor, his company commander. They had two sons, one of whom, James Harper Gillett, became the first American bullfighter in Mexico (under the name Harper Lee). The marriage ended in divorce. In December 1881 Gillett resigned from the Texas Rangers and was appointed assistant city marshal of El Paso. In June 1882 he was appointed marshal. El Paso at that time was a town of many saloons and gambling houses, a gathering place for outlaws, gunmen, and desperadoes. Gillett, still in his twenties, was known as a man without fear. He reportedly did not swear or drink, but claimed that "no man will ever kill me drunk." On April 1, 1885, after having clubbed a city councilman with a six-shooter, he left the El Paso marshal's office and became manager of the Estado Land and Cattle Company. He held this position for almost six years, then resigned to ranch for himself. On May 1, 1889, Gillett married Lou Chastain in San Marcos. They had seven children.
Gillett ranched south of Alpine on the O6 and Altuda ranches. In May 1904 he sold the Altuda, acquired an alfalfa farm near Roswell, New Mexico, and moved his family there. A year later he sold the O6 Ranch. After farming for three years Gillett decided he was not suited for it. He sold the farm in April 1907 and moved his family back to Texas. He bought the Barrell Springs Ranch, made improvements, and began building a herd of registered Hereford cattle, which became well known for quality and brought premium prices. He wrote Six Years with The Texas Rangers (1921); it was republished in 1926 by Yale Press and in 1976 by the University of Nebraska Press. In 1928 it was condensed under the title The Texas Rangers and was used as a textbook in the public schools of seventeen states. Gillett retired at age sixty-seven, leased the ranch, sold his cattle to his son Milton, and moved to Marfa. He was a member of the Alpine Masonic lodge, a thirty-second-degree Scottish Rite Mason, director of the Marfa National Bank, and for many years the president of the Bloys Camp Meeting. He helped organize the West Texas Historical Association, was instrumental in organizing the Highland Hereford Breeders Association, and was a member of the First Christian Church. He died at Temple of heart failure on June 11, 1937, and was buried in the Marfa Cemetery. There is a Texas historical marker at his gravesite.