The O Bar O Ranch, which in 1990 covered approximately 100 square miles between the Salt Fork and Double Mountain Fork of the Brazos in central Kent County, traces its origin to 1874, when Jesse Hittson registered a Two Circles Bar brand, consisting of two circles with a bar running under them. At that time he and his father, John Hittson, had moved their cattle out of Palo Pinto County to their Six Springs Ranch in Colorado. About 1878 Jesse bought 5,000 Mexican cattle in South Texas and branded them with this peculiar mark. In October 1879 he and ten cowboys moved them north to the Double Mountain Fork of the Brazos, into an isolated area of cedar breaks containing several spring-fed tributaries. The Circles Bar headquarters was established near the mouth of one of these tributaries, Rough Creek, in northwestern Fisher County. An abandoned dugout built there by buffalo hunters served as a temporary ranchhouse until completion of the permanent headquarters, a three-room structure with porches on two sides built out of lumber hauled from Colorado City. Alec Moore, who was designated range boss, located five line camps in areas near suitable water and provisioned them from headquarters. The first roundup on the Circles Bar occurred in 1880.
Hittson had set up this ranch as a wintering ground for steers to be moved to his Colorado ranges in the spring. In 1883 he sold the Circles Bar brand and cattle for $200,000 to O. J. Wiren, who made them the basis of his short-lived fortune. Under Wiren's supervision ranchlands were bought or leased and fences erected along the perimeters of the ranch. "Uncle Jimmy" Adair, a former buffalo hunter, served as headquarters manager. The colorful Jim Cook, alias Jim Lane, served as wagon boss and was said to have owned an interest in the Circles Bar. J. T. Bond, who helped fence the range, began riding herd for Wiren in 1886 and stayed on with the ranch for many years. By the mid-1880s some 30,000 cattle bearing the Two Circles Bar were grazing over 500 square miles of grassland in Kent, Stonewall, Fisher, and Scurry counties.
Despite his improvements, mounting expenses, hard winters, drought, and declining cattle prices caused Wiren's fortune to wane. In 1889 he sold his property by auction in Colorado City to his creditors, George Kellog, Horace W. Mccoy, and Lyman Rumery of Oshkosh, Wisconsin. Under their ownership fences were improved, and purebred shorthorn bulls were brought in from the JA Ranch to build the herd. A. W. Hudson was appointed manager, and Charley Binnion and Roy Davis served successively as wagon bosses. During that time the Circles Bar ranges covered some 300,000 acres, making it the fourth largest ranch in Texas. Although the Circles Bar enjoyed a period of prosperity, a division among its owners resulted in its being sold for $105,000 to Dorn Clark and D. C. Plumb in December 1894. Part of the ranch's southern range, including the headquarters on Rough Creek, wound up as the property of the Half Circle S, the new ranching venture begun by Hudson and his partner, Doc Shultz. After Clark and Plumb purchased the old Ten Ranch in north central Kent County from its English owner, Capt. Freeville Cooksen, its headquarters on Duck Creek became the permanent nucleus for the Circles Bar. About 20,000 calves were branded during the roundup season in 1895. However, Clark and Plumb sold out to Henry G. Weare of Spearfish, South Dakota, in November 1895, and in March 1898 Weare sold to Charles L. Ware. These owners were more interested in the land value of the Circles Bar than in actually raising cattle, and by 1900 only a remnant of the herd remained on the ranch.
This rapid succession of owners ended in the spring of 1900, when John S. Bilby, from Missouri, contracted to buy the Circles Bar land and cattle. In 1901 Bilby altered the brand by placing the bar between the two circles. Over the next two decades the O Bar O ran 15,000 cattle over much of Wiren's original range; at the same time parcels of land were sold to settlers as railroads came in, and towns like Clairemont and Jayton sprang up. Initially Bilby, who was a shrewd and capable businessman, had formed a partnership with John A. Wishard, who imported about 300 hired laborers from Japan and built for them a small town near the headquarters east of Clairemont. Wishard had planned to build up his own empire on the O Bar O, but when his schemes failed he tried to abscond with vendor's lien notes and records from the ranch office. Bilby detected the theft and followed his wayward partner to Fort Worth. In the lawsuit that followed Bilby won, and the partnership was terminated. By the early 1920s the former Circles Bar range had been broken up, and much of it sold to farmers and smaller ranchers. The nucleus of the O Bar O Ranch in Kent County became the property of Bert Wallace, a grandson of John S. Bilby, who in turn passed it on to his son, Bilby Wallace. In 1990 the ranch was owned and operated by Wallace heirs.