Birmingham-born R.G. Armstrong attended the University of North Carolina-Chapel Hill, where he was active with the Carolina Playmakers. On the New York stage since the 1940s, Armstrong is best remembered for creating the role of Big Daddy in the original 1955 Broadway production of Cat on a Hot Tin Roof. In film since 1957, Armstrong appeared in more than his share of westerns, usually as an able-bodied sheriff or thick-necked land baron. A frequent visitor to television, R. G. Armstrong was a regular on the 1967 adventure series T.H.E. Cat.