Mitchell County is in the prairie of west central Texas, bounded on the east by Nolan County, on the south by Sterling and Coke counties, on the west by Howard County, and on the north by Scurry County. The county center is at 32°18' north latitude and 100°55' west longitude. Colorado City, the largest town, is in the northeastern part of the county, roughly 229 miles west of Fort Worth. The area was named for Asa and Eli Mitchell , prominent participants in the Texas Revolution. The county embraces 912 square miles of prairieland surfaced mainly with sandy, red, and dark soils. The altitudes range from 2,004 to 2,616 feet above sea level. The main physical feature is the Colorado River, which enters the county from the north and flows through the center. The river traverses the Callahan Divide, a line of hills that extends from east to west in the southern part of the county. In the county are several lakes, including Lake Colorado City, Champion Creek Reservoir, Lake Gregory, and Lake Butler, all of which are recreational sites. Wild china, live oak, willow cedar, black walnut, pecan, and other trees grow in the area; grasses include bunchgrass, shortgrass, grama, needlegrass, and Johnson grass. During the spring Mitchell County sports a variety of wildflowers, including buttercups, daisies, sunflowers, and honeysuckle. Rabbits, prairie dogs, coyotes, and wolves are found in the area. The most common reptile is the rattlesnake. Temperatures in the county range from an average high of 96° F in July to an average low of 30° in January, rainfall averages 19.68 inches a year, and the growing season lasts 217 days. The county is served by Interstate Highway 20, which runs from west to east, and by State highways 163 (north to south) and 208 (north to southeast). The Missouri Pacific Railroad runs east to west across the county, through Colorado City.
The history of Mitchell County in the seventeenth, eighteenth, and nineteenth centuries was characterized by Spanish exploration and Indian domination. Because of their interest in the Jumano Indians, the Spanish made a series of expeditions through West Texas in the seventeenth century. Though no major explorations took place in what is now Mitchell County, the expeditions traveled through the area. In 1629 and 1632, Fr. Juan de Salas led expeditions to the Jumanos. Captains Hernán Martín and Diego del Castillo made an expedition through West Texas in 1650 in search of the Jumanos, as did Diego de Guadalajara, sent to find wealth, in 1654. Comanches of the Penateka band settled in the region in 1780 and controlled the area of the future Mitchell County until 1875, when Ranald S. Mackenzie of the United States Army moved them onto reservations.
In 1876 the Texas legislature formed Mitchell County from the Bexar District; since it had virtually no permanent settlers at the time, the county was assigned to Shackelford County for administrative purposes. During the late 1870s settlers began to enter. The early settlers in the county, mostly buffalo hunters, included J. Wright and John W. Mooar , George Wandell, and I. F. Byler. In 1880 the census counted 112 residents in the county. As a result of population growth in the late 1870s, elections were held on January 10, 1881, to organize Mitchell County. Colorado City was chosen the county seat, and J. R. Dobbins became the first county judge. A. W. Dunn, generally known as the "father" of Colorado City because he owned the first store there, became the first county treasurer. Cattlemen first moved into the county with their herds in the late 1870s; until the early twentieth century the economy of Mitchell County was dominated by cattle ranching.
During the settlement period merchants and traders also occupied the county, anticipating the construction of a railroad through the area. In the early 1880s the Texas and Pacific Railway was built through the county to Colorado City, and by April 16, 1881, the day the first train arrived, that town's population had reached 300. By 1882 four railroad stations had been established in the county. The railroad led to an instant boom in Colorado City; between 1881 and 1885 the town grew rapidly in population and prosperity. In 1881 the Colorado Courant, a weekly paper, began publication. Ranches were inaugurated in different parts of the county. Within this four-year period Colorado City emerged as a major shipping center to rival Dodge City and Abilene as a cattle town. By 1884 it had several saloons and beer parlors, scores of general stores, lawyers, doctors, and a population of about 3,000.
The boom died, however, partly as a result of a series of natural disasters in the late 1880s and 1890s. The first major setback was the severe drought of 1886, which was followed by the most terrible winter of the decade; cattle starved. In 1890 the agricultural census counted thirty-five farms and ranches in the county, but only 2,645 cattle were reported that year. That year only 124 acres of county land was planted in corn, the county's most important crop. According to the United States Census Bureau, 2,059 people were living in the county in 1890. Other droughts occurred in 1892, 1893, 1894, and 1897. In the late 1890s and early 1900s Colorado City was bypassed by three railroad lines (the Fort Worth and Denver, the Roscoe, Snyder and Pacific, and the Santa Fe), and the population and businesses of the town continued to decline. By 1900 Colorado City had lost its prominence as a cattle town, and the previous commercial importance of Mitchell County had passed. Ranching remained at the center of the local economy, but farmers were beginning to establish themselves in the area. In 1900 more than 60,000 cattle were reported on 232 farms and ranches. About 1,000 acres was planted in corn in 1900, and 3,105 acres was devoted to cotton. Meanwhile, the population of the county had grown since 1890 to reach 2,855.
The climate of Mitchell County was and is suitable for the cultivation of cotton and sorghum. Cotton, first planted in the county in 1898, became the leading crop after 1900. In 1910 more than 32,000 acres of county land was dedicated to cotton production. By 1920 cotton was planted on almost 48,000 acres of land in the county, and another 17,395 acres was devoted to sorghum culture. By 1930 cotton was being grown on more than 132,000 acres. Though cattle ranching had steadily declined in relative importance, it still remained an important part of the local economy. In 1930, near the peak of this early cotton boom, there were about 28,000 cattle in the county. The general expansion of farming in the area drew thousands of new settlers to the county during the first thirty years of the twentieth century. The number of farms in Mitchell County increased from 232 in 1900 to 1,108 by 1910. Droughts and the post–World War I agricultural depression drove some farmers out toward the end of the decade, but the boom resumed in the 1920s, as farms multiplied and cotton production continued to expand. The number of farms in the county grew from 864 in 1920 to 1,339 in 1925 and 1,481 by 1930; 1,064 of these were run by tenant farmers. Accordingly, the population rose to 9,859 by 1910, dropped to 7,527 by 1920, and rose again to 14,183 by 1930.
The economy suffered serious reverses during the Great Depression of the 1930s. Droughts and regulation of crop production by the federal government combined to drive down cotton acreage by about 50 percent over the course of the decade; by 1940 only 65,479 acres in the county was devoted to growing the fiber. The crop reductions particularly hurt the tenant farmers. By 1940 the number of farms in Mitchell County had dropped to 1,119, and 604 of these were operated by tenants. These developments drove down the population of the county to 12,477 by 1940.
Oil, discovered in the county in 1920, helped to stabilize the economy during the 1930s; after World War II it became an important source of jobs and income, even after petroleum prices plunged during the 1980s. Production of crude petroleum in Mitchell County exceeded 390,000 barrels in 1938 and reached almost 538,000 barrels in 1944. It was 803,184 barrels in 1948, 2,413,916 barrels in 1956, 2,512,965 barrels in 1960, and 5,094,682 barrels in 1974. It exceeded 6,500,000 barrels in 1982 and 4,889,200 barrels in 1990. By January 1, 1991, 176,890,444 barrels of crude had been taken from Mitchell County lands since discovery in 1920.
Cotton and sorghum continued to be the main source of agricultural revenue for the county, which in 1982 produced 27,319 bales of cotton, 18,116 tons of dry hay, 93,040 bushels of sorghum, and 28,027 bushels of wheat. Ranching also remained important. In 1982 Mitchell County produced 22,389 cattle and calves, 438 hogs and pigs, 7,376 sheep and lambs, 651 horses and ponies, and 50,855 pounds of wool. In 1985 the county obtained $14 million from beef cattle, hogs, sheep, horses, dairy products, poultry, cotton, sorghums, and small grains. Its 4,000 acres of irrigated land was used for both pasture and cultivation.
Despite the oil production, the mechanization of agriculture and the decline of the family farm contributed to a general population decline in the county after the 1950s. The census counted 15,357 people living in Mitchell County in 1950, 11,255 in 1960, 9,073 in 1970, 9,088 in 1980, and 8,016 in 1990. As of 2014, 9,076 people live in the county. Of those, 48.2 percent were Anglo, 12.8 percent African American, and 38.7 percent Hispanic. The voters of the county supported Democratic candidates in virtually every presidential election between 1888 and 1968; the only exception occurred in 1928, when they supported Republican Herbert Hoover over the Catholic Democrat Al Smith. Between 1972 and 1992 a majority of the county's voters increasingly voted Republican; they supported Richard Nixon in 1972 and Ronald Reagan in 1980 and 1984. In the 1992 presidential election, a plurality of county voters supported Democrat Bill Clinton over Republican George H. W. Bush and independent candidate Ross Perot. Communities in Mitchell County include the county seat, Colorado City (population, 4,025), Loraine (592), Westbrook (245), and Buford. Recreational sites include Lake Colorado City State Recreation Area, Champion Creek Reservoir, and the Colorado City Museum.