In 1941, he received his Ph.D. in history from Columbia University and enlisted in the US Navy as an Ensign; he mustered out in 1946 holding the rank of Lieutenant Commander.
He received his Ph.D. in history from Columbia University. This was in 1941. He enlisted in the US Navy as an Ensign. This was in 1941. He mustered out in 1946. He was holding the rank of Lieutenant Commander.