Michael J. O’Brien was born in Houston in 1950 and graduated from St. Thomas High School in Houston in 1968.
His undergraduate degree is from Rice University (1972) and his Ph.D. from the University of Texas at Austin (1977). After graduation he served as a research associate at the University of Nebraska–Lincoln until 1980, when he joined the University of Missouri as an assistant professor of anthropology and director of the American Archaeology Division, the research arm of the anthropology department. He became director of the Museum of Anthropology several years later and joined the College of Arts and Science dean’s office as associate dean for research. He was promoted to the rank of professor in 1989 and became dean of arts and science in 2006 following a national search.