The Handbook of Texas Online has an excellent biography:
Burk Burnett, rancher, banker, oilman, son of Jeremiah (Jerry) and Nancy (Turner) Burnett, was born on January 1, 1849, in Bates County, Missouri. In the late 1850s the family moved to Texas and built a home on the banks of Denton Creek in Denton County. Within ten years Jerry Burnett had established a small but successful ranch that enabled Burnett to learn the day-to-day operations of the cattle business. Burk received little formal schooling, but he used his practical education to become eventually one of the wealthiest ranchers in Texas. His first trail drive occurred in 1866. The following year he served as trail boss, driving his father's 1,200 cattle along the Chisholm Trail to Abilene. In 1868 he became a partner with his father, and in 1871 he acquired his own brand and began building what became one of the largest cattle empires in Texas history—the Four Sixes Ranch. Burnett weathered the panic of 1873 by holding over the winter the 1,100 cattle he had driven to Kansas. The following year he sold this stock for a profit of $10,000. He was one of the first ranchers in Texas to buy steers and graze them for market. At first his herd consisted of longhorn cattle, but later he introduced Durhams and then Herefords into the herd, thus producing what many considered to be among the finest cattle strains in the state.
In 1874 Burnett bought and moved cattle from South Texas to the area of Little Wichita, now Wichita Falls, where he established his ranch headquarters in 1881. The move was partly prompted by the increase in the number of Four Sixes cattle and an agreement drawn up between Burnett and Quanah Parker, Comanche chief and friend of Burnett. Through Parker's assistance over a period of years Burnett leased 300,000 acres of Kiowa and Comanche land in Indian Territory for 6½ cents an acre. He grazed 10,000 cattle on this land until 1902. After 1898 cattlemen were told to surrender their lease agreements to allow opening of Oklahoma Territory to homesteaders. Burnett once again called on a friend for assistance, this time Theodore Roosevelt. The Texas rancher asked the president for an extension so that the Texas cattle might be removed in an orderly fashion. Roosevelt's agreement to the request enabled Burnett to purchase land to offset the loss of grazing rights in Oklahoma. Between 1900 and 1903 Burnett purchased 107,520 acres in Carson County northeast of Amarillo and bought the Old "8" Ranch, of 141,000 acres, near Guthrie in King County, ninety-three miles east of Lubbock. The two purchases increased the size of the Four Sixes to 206,000 acres. Ultimately, Burnett owned ranches in Oklahoma and Mexico in addition to his holdings in Texas and ran 20,000 cattle under the Four Sixes brand.
In 1905, in return for Roosevelt's assistance, Burnett helped organize a wolf hunt for the president. During the president's visit, Roosevelt influenced the changing of the name of Nesterville, on the Four Sixes spread in Wichita County, to Burkburnett. Five years later Burnett discontinued personal direction of his ranch. He leased the Four Sixes to his eldest son, Tom, so that he could concentrate his attention on his other businesses, banking and oil. After the discovery of oil on land near Burkburnett in 1921, Burnett's wealth increased dramatically. He had already expanded his business interests by buying property in Fort Worth, where he had maintained a residence since 1900. By 1910 the city had become headquarters for his financial enterprises, and he had become the director and principal stockholder of the First National Bank of Fort Worth and president of the Ardmore Oil Milling and Gin Company. He continued his interest in ranching, however, through his association with the Stock-Raisers Association of North-West Texas. He had been a charter member in 1877, and he served as treasurer from 1900 to 1922. Burnett was also president of the National Feeders and Breeders Association and in 1896 of the Fort Worth Fat Stock Show (later the Southwestern Exposition and Livestock Show).
Burnett married Ruth B. Loyd in 1869, and they had three children. They were later divorced. Two of their children, Ann and Thomas L. Burnett, lived to adulthood. Burnett married Mary Couts Barradel of Weatherford in 1892, and this couple had one son. In the early 1920s Burnett's health failed and he went into semi-retirement. On June 27, 1922, he died. At the time of his death his wealth was estimated at $6 million, part of which, through the efforts of his widow, became an endowment for Texas Christian University.
Burk Burnett was inducted into the Texas Trail of Fame in the Fort Worth Stockyards in 1997, and his star is in front of The Coliseum.