Robert Norville Mullin (August 10, 1893 – June 27, 1982) was born in Lincoln, Nebraska, and moved to El Paso, Texas, in 1900. His father was an educator, and his mother was the daughter of Captain William N. Norville, who served in the Union Army. Mullin graduated from El Paso High School in 1912, where he wrote a children's play.
Mullin established himself as a businessman and public figure in El Paso, founding the Calmut Oil Company (COC) in 1917.