Jim Cook, cattleman and raconteur, son of Mart Cook, was born on February 25, 1861, in Washington County, Arkansas. When the Civil War broke out, Mart enlisted in the Confederate Army and served as a captain under Gen. Sterling Price. Afterward he moved to Texas, rounded up cattle, and sought out a market in Kansas. Jim and his brother Al grew up in the saddle. In 1866 the Cooks were perhaps among the first to drive cattle north to Honeywell, Kansas. The boys' mother died later that year, and their father was reportedly killed by Indians in 1867. Jim and Al went to live with an uncle and cousin who were also ranchers. Until 1876 Jim remained at his uncle's ranch; he was then put in charge of a herd of 1,000 steers to be trailed north to Kansas and fattened on the grasslands there. While on the trail, according to his earliest account, some of Cook's fellow cowboys started calling him Jim Lane and Kid Boss. The nicknames stuck with him for several years. In the fall of 1876 Cook and a partner started their own ranch on the South Fork of the Llano River in Kimball County. Cook remained there until 1880, when he sold his interest.
Both Jim and Al, who sometimes went by the alias of Taylor Williams, worked for O. J. Wiren, foreman of the Quitaque Ranch. In 1881, when the Quitaque was sold to Charles Goodnight and Wiren purchased the Two Circle Bar on the upper Brazos from Jesse Hitson, the Cooks stayed with Wiren. Indeed, Jim "Lane," who was made wagon boss, was said to have owned an interest in the Two Circle Bar, although the records show no such evidence. He reportedly ran his own herd at the ranch and won notoriety among the cowboys as a "hard man to work for and inconsiderate of his men." However, he remained with Wiren five years before leaving "for reasons of my own," as he later stated. At that time Cook reportedly "put a notice in the Fisher County Call refusing to answer to Lane any more to anyone."
In 1888 he was hired by the Capitol Freehold Company as foreman for the XIT Ranch's Escarbada Division. Aggressive and overbearing and often carrying a pair of six-shooters, Cook was nearly always at odds with cow thieves from "across the line" and occasionally with his own men. When he met a visiting young lady from Kansas City at La Plata, he fell in love with her, and according to several old cowboys, was instrumental in getting the Escarbada headquarters declared a post office so that letters from his lady would be delivered directly to him. Eventually they were married.
When Deaf Smith County was organized on October 3, 1890, Cook was elected its first sheriff, but he was ousted a year later because of his needless killing of a cowboy. In later years he boasted that since La Plata had no cemetery he had to "kill a man to start one." Whether or not this was true, he was finally acquitted after judicial wrangling and a change of venue to Amarillo. Possibly to escape the effects of the scandal, Cook and his wife turned up in South Dakota for a short time and then homesteaded near Monument, New Mexico. They became the parents of a daughter, whom Cook managed to raise after his wife died. His brother, Al, eventually made his home in Las Cruces.
Beginning in the early 1900s, Jim Cook traveled throughout the western United States and Canada, prospecting and working as a wilderness-park guide in his attempt to find or re-create the way of life he had known during the early years of the Cattle Kingdom. In 1912 he published a booklet entitled The Canadian Northwest as It Is Today, in which he described his experiences on a pack trip into the Canadian wilds in 1910–11. Cook's eccentricities increased in the 1920s when he proposed to open a central detective agency in Austin to recover stolen cattle, an information bureau to locate choice homesteads, and a home for aged cowboys. As he recounted his early adventures to enthralled listeners, facts became submerged in plausible fantasy. He made his later travels in a battered Model T with his daughter and two granddaughters.
While Cook was living in Albuquerque during the 1930s, T. M. Pearce of the University of New Mexico conducted a series of interviews with him for the New Mexico Folklore Society. These formed the basis for the book Lane of the Llano (1936). In this work Cook related his alleged birth in Llano County in 1858, his capture by Comanches as a boy, his wanderings with the tribe and marriage to the chief's daughter White Swan, his role as a scout in Ranald S. Mackenzie's Palo Duro campaign, his alleged involvement with John S. Chisum and Billy the Kid (see MCCARTY, HENRY), and the death of White Swan from a rattlesnake bite, all mixed with convincing descriptions of the arid land, with its flora and fauna and harsh realities. One contemporary called the book "a bunch of the worst lies that would make Bill Burns, Zane Grey, and John Cook green with envy," and J. Evetts Haley admitted that an accurate biography of Cook could never be written as long as the man failed to distinguish between truth and fiction. However, for the remainder of his life, Jim Cook was lionized by college students, faculty, and others who saw him as a living symbol of the vanished frontier. He died in January 1940 and was buried in the Oddfellows Cemetery in Goldthwaite.