William D. Leahy
William Daniel Leahy ( LAY-(h)ee; 6 May 1875 – 20 July 1959) was an American naval officer and was the most senior United States military officer on active duty during World War II; he held several titles and exercised considerable influence over foreign and military policy. As a fleet admiral, he was the first flag officer ever to hold a five-star rank in the U.S. Armed Forces.