Known as Mike to his colleagues at Princeton. Went to Princeton from the Evanston Township High School in Illinois as a member of the class of 1925. He graduated summa cum laude in classics, earning his A.M. in 1927 and his Ph.D in 1931. Chairman of the classics department for sixteen years. Published extensively in his special fields of interest, Greek drama and philosophy. In the 1930s he was a principal organizer, and from 1945 to 1959 was chairman, of the Special Program for the Humanities. During World War II, Oates served with the Marines in the Southwest Pacific. He returned to Princeton in 1945 and conceived and found the money for a plan to attract returning servicemen into college teaching, founding a program that became the National Woodrow Wilson Fellowship Program.
In 1953 he helped establish the Council of Humanities and was chairman until his retirement from the faculty in 1970.