Leonard J. Arrington was born on July 2, 1917 in Twin Falls, Idaho. He was raised on a farm in Idaho and attended the University of Idaho where he majored in agricultural economics. He began working towards a doctorate degree in economics from the University of North Carolina at Chapel Hill, but his studies were cut short when he was drafted in 1943. That same year Arrington married Grace Fort (they would have three children; James, Carl and Susan.) Arrington served overseas in North Africa and Italy until 1946. After the war he began teaching at the Utah State Agricultural College and except for one year spent in Chapel Hill to complete his doctorate, one year teaching in Italy, and one at UCLA, Arrington would continue to teach at Utah State University until 1972. Between 1972 and 1982 be began working as the L.D.S. Church Historian. In 1982 Grace passed away, and in 1983 he and Harriet Horn were married. Arrington died on February 11, 1999 due to heart failure.

Dr. Arrington was a prolific writer. He began by publishing articles on nineteenth century Mormon economics, but he soon branched out into other L.D.S.History topics as well as Mormon biography. Some of his better known books include Great Basin Kingdom (1958), The Mormon Experience: A History of the Latter-Day Saints (1979), and Brigham Young: American Moses (1985). Arrington was also a leader as a professional historian. He helped to establish the Mormon History Association (serving as its first president) and the Western Historical Quarterly. He also served as president of the Western History Association and the Pacific Coast Branch of the American Historical Association.