Dr. Riley started his education in a one-room schoolhouse before attending Southeast Missouri State University. He served in England with the air division of the U.S. Army during World War II. After discharge from the U.S. Army, he entered the University of New Mexico, where he received his bachelor's degree with honors in 1948. In 1950 he was awarded his master's degree at the University of California Los Angeles, followed by a PhD at UNM in 1952.
Riley worked summers as a ranger for the National Park Service in Mesa Verde National Park and Hovenweep National Monument. While gathering data for his dissertation, he lived among and studied the jungle-dwelling Panare people in Venezuela.
From 1952 to 1955, Riley served as a consultant to the United States Department of Justice Land Division.
Riley began his teaching career at University of Colorado at Boulder and University of North Carolina at Chapel Hill. In 1955, he was offered a position at Southern Illinois University Carbondale, where he spent the bulk of his professional life.
Dr. Riley received several major awards, including Historic Preservation Award in 1985 with Charles and Elizabeth Lange for their work on the Southwest Journals of Adolph P. Bandelier, and Distinguished Lifetime Achievement Award in 2015 from the New Mexico Department of Cultural Affairs, Preservation Division. Dr. Riley died in 2017 at his home in Las Vegas, New Mexico.