[1] In 1942, Mamatey enlisted into the United States Army Air Corps and served in the China-India-Burma theatre.
At the University of Georgia he assumed the duties of research professor and served for a year in 1972, and 1973 as acting dean of the Franklin College of Arts and Sciences.
A recognized expert in East European history, Mamatey authored, co-authored and edited a number of books and other publications, including The World in the Twentieth Century (Boston, 1962).
He won the American Historical Association's George Louis Beer Prize in 1958 for The United States and East Central Europe,[2] and a Guggenheim fellowship.
Mamatey supported the University Library in Bratislava, Slovakia, to which he regularly sent large volumes of books on Slavic studies he had collected.