William V. O'Regan

William Vincent O'Regan (25 April 1900 – 13 January 1978) was a decorated submarine commander during World War II who reached the rank of Vice Admiral in the United States Navy.

O'Regan was trained as a submarine engineering officer, serving aboard submarines or at submarine bases, but never given an individual submarine to command. Instead, he eventually commanded groups of submarines and other vessels. During World War II, he was given command of Submarine Squadron Four consisting of , , and . "Mickey" O'Regan successfully led his "Mickey Finns" on a patrol near Formosa in the East China Sea in June–July 1944. The destruction of enemy shipping by his submarines earned him a Navy Cross. He was also awarded the Legion of Merit for his full wartime service. They had two sons and five grandchildren.