Ruth Elizabeth "Bazy" Tankersley (March 7, 1921 – February 5, 2013) was an American breeder of Arabian horses and a newspaper publisher. She was a daughter of U.S. Senator Joseph Medill McCormick. Her mother was progressive Republican U.S. Representative Ruth Hanna McCormick, making Tankersley a granddaughter of the Senator Mark Hanna of Ohio. Although Tankersley was involved with conservative Republican causes as a young woman, including a friendship with Senator Joseph McCarthy, her progressive roots reemerged in later years; by the 21st century, she had become a strong supporter of environmental causes and backed Barack Obama for president in 2008.
Tankersley's father died when she was a child. When her mother remarried, the family moved to the southwestern United States where Tankersley spent considerable time riding horses. She became particularly enamored of the Arabian breed after she was given a part-Arabian to ride. At 18 she began working as a reporter for a newspaper published by her mother. She later ran a newspaper in Illinois with her first husband, Peter Miller, and then in 1949 she became the publisher of the conservative Washington Times-Herald. That paper was owned by her uncle, the childless Robert McCormick, who viewed Tankersley as his heir until the two had a falling out over editorial control of the newspaper and her relationship with Garvin Tankersley, who became her second husband. After The Washington Post absorbed the Times-Herald, she shifted to full-time horse breeding.
Tankersley purchased her first purebred Arabian when she was 19, and began her horse breeding operation, Al-Marah Arabians, in Tucson, Arizona, in 1941. As she moved across the US for her newspaper career, her horses and farm name went with her. She purchased her program's foundation sire, Indraff, in 1947, while living in Illinois. Upon her move to Washington, DC, her Al-Marah operation relocated to Montgomery County, Maryland, where by 1957 it was the largest Arabian farm in the United States. Tankersley returned to Tucson in the 1970s, where in addition to horse breeding, she created an apprenticeship program at Al-Marah to train young people for jobs in the horse industry. She set up a second horse operation, the Hat Ranch, near Flagstaff, Arizona. Over her career she bred over 2,800 registered Arabians and was one of the largest importers of horses from the Crabbet Arabian Stud in England.
Tankersley was a patron of many charities. Upon her death from Parkinson's disease in 2013 she bequeathed her Tucson ranch to the University of Arizona and placed the Hat Ranch in a conservation trust. In her final years, she downsized her breeding operation to about 150 horses, and most remaining stock went to her son, Mark Miller, who moved the Al-Marah Arabian farm name and horse operation to his home base near Clermont, Florida.