John L. Kessell is a co-author of Father Kino in Arizona, and a contributor to the New Mexico Historical Review, Arizona and the West, and the Journal of Arizona History. A visiting assistant professor of history at the University of New Mexico in 1969-70, he holds a Ph.D. degree from that institution. He is a graduate of Fresno State College, and took his M.A. degree at the University of California, Berkeley. It was while serving as historian at Tumacácori National Monument, Arizona, that he recognized the need for a history of Mission Guevavi.