The region around Cat Creek was largely unsettled until the 1860s, although
River Crows and
Ventre Indian hunters and trappers
migrated through the area. Fort Musselshell
trading post was built in
Mosby, Montana,
Garfield County, on the Missouri River, to the east. In the 1860s and 1870s, Fort Musselshell was a
supply depot for "woodchoppers" and lumbermen who worked for the Missouri River
steamboats, and as a trading post for hunters, trappers and Indian trappers. The fort had a colorful history with
Assiniboine and
Sioux Indian attacks and becoming briefly, a
cattle rustlers hangout that ended when a
Vigilance Committee hanged a few rustlers. Local legend had it that a cowboy roped a mountain lion in a creek flowing into the Musselshell River, giving rise to the name, Cat Creek. The area known as Cat Creek Basin was also referred to as the Shay community from 1910 to 1920, after one of the early homesteaders, who deeded land for a school and cemetery in his name. In late 1919, the
Frantz Corporation began oil exploration on a creek near Winnett, Montana, flowing into the Musselshell River. The first major commercial oil field discovery in Montana was at the West Dome of the
Cat Creek field, Eastern Fergus County, at a depth of . The oil was considered "the highest grade of oil known to any oil fields." The discovery well, named "Antelope No. 1," was showing oil in November 1919 and put into full use by the Frantz Corporation on February 19, 1920. John S. "Curley" Meek, one of the first drillers in the Cat Creek area, stated that "there was no place to store the oil, so it was dammed up in a
coulee and given away to ranchers and farmers as
sheep and cow dip until they began using it in their cars." Due to a lack of storage facilities, the oil was directed into a coulee, where it became a tourist attraction; it was of such a high quality that tractors and
Ford Model T automobiles could run on the oil directly from the ground, which was distributed free of charge to everyone. Storage tanks were soon constructed; during the summer of 1920, the Frantz Corporation constructed a diameter pipeline to carry the oil to Winnett. With the excitement over the discovery of oil at Cat Creek, and frenzy to develop the oil field by independent interests, a study of the 75 townships in the area was undertaken by the
U.S. Geological Survey during the summers of 1920 and 1921. The subsequent report, published in 1926, involved the collection of information for use in the administration of the Federal oil leasing law. The report established the government's interest in the area with the results of field work that could be used in the development of the recently discovered Cat Creek and Devils Basin oil fields, and the search for new fields. The area surrounding Cat Creek is very isolated; supplies were hauled from Winnett, the only large settlement in the area, to the west of the oil field, to the site by wagon and horses. By May 1920, production from one well, drilled to a depth of , had totaled up to 200 barrels a day. In April 1921, 30 producing wells owned by six different companies, were at work. In a "raw, roaring oil camp", A post office was established in Cat Creek in 1922, remaining active until 1996. With the continued development of the Cat Creek oil fields and the resultant increase in the area's population, the
Montana Legislature voted on November 24, 1924, to form a new county, sectioned off from eastern
Fergus County and western Garfield County. Petroleum County officially became Montana's 56th and final county in February 1925. Winnett, with a population in 1923 of 2,000, became the county seat. The Elk Basin Consolidated Petroleum Company later sold the Cat Creek field in 1924 to
Mutual Oil Company of
Casper, Wyoming, for $450,000. In turn, Mutual Oil sold the field in 1938 to
Continental Oil, an oil distributor from
Ogden, Utah. After the lucrative oil wells stopped producing in 1975, the community of Cat Creek began to deteriorate as jobs also dried up, with an estimated population of only 494 (2010) residents in Petroleum County. ==References==