Clifton Mott Caldwell, philanthropist, oilman, and rancher, son of James S. and Janie (Mott) Caldwell, was born in Palo Pinto County, Texas, on May 1, 1880. He spent his early years working on the family farm with his three brothers, and by attending rural and summer normal schools he earned a teaching certificate. In 1896 he moved with his family to Breckenridge, where he met his future wife, Cora Belle Keathley. They were married in 1901 and soon moved to Caddo, where, after teaching for five years, Caldwell became the principal of the Caddo school. In 1908 he moved his wife and three children to Austin, and at the age of twenty-eight, with a total of $400 in savings, he entered the University of Texas law school. After he graduated in 1911 the family returned to Breckenridge, where in 1912 Caldwell was elected county attorney of Stephens County. He served until 1916. In the four years that followed he was appointed county judge and later district judge.
In 1917 Caldwell and his partner, Breck Walker, formed the Walker-Caldwell Oil Company, which was highly successful during the Ranger and Breckenridge oil booms. Caldwell acquired large landholdings in West Texas, and both he and Walker invested much of their time and profits in the future of Breckenridge. They financed the city's first water system and induced three railroads to come to town. In the 1920s and again in the 1950s Caldwell served as director of the Texas and Pacific Railway.
In 1922 the family moved to Abilene, where Caldwell had close ties through his work in the Baptist Church and his friendship with Jefferson Davis Sandefer, president of Simmons College (now Hardin-Simmons University). Caldwell served as chairman of the Hardin-Simmons board of trustees for many years, and as a member until his resignation at the age of eighty-five. In 1923 Governor Pat Neff appointed him a regent of the University of Texas, and he served on both the land and publicity committees. In 1929 Governor Daniel Moody appointed Caldwell founding director of the Brazos River Authority, a post he held for the next twenty-five years. Caldwell also donated the land for Hendrick Memorial Hospital (now Hendrick Medical Center) in Abilene, contributed funds for its operation, and served as a trustee for decades. He was a member of the boards of Citizens National Bank and Abilene Savings Association for over forty years. During both world wars he chaired county war loan drives; during World War II he raised more than $40 million in bonds and stamps in Taylor County. In 1951 Caldwell was presented the "Top Citizen of the Year" award, the highest civic honor awarded by the Abilene Chamber of Commerce. He died on August 8, 1968, at the age of eighty-eight.