 Warburton was born in Wilmington, Delaware.He attended the public schools of Wilmington, and Reading, Pennsylvania, and graduated from the University of Delaware in Newark, Delaware in 1938, and from Dickinson School of Law in Carlisle, Pennsylvania in 1941.An ROTC graduate from the University of Delaware, he was commissioned a second lieutenant, and began active Army duty as first lieutenant of the One Hundred and Twenty-second Antiaircraft Battalion in September 1941.