In September 1943 he became Commander Amphibious Group Two, Fifth Amphibious Force, and in that capacity participated in the capture of Tarawa, and later in operations against the Gilberts, Marshalls, Marianas, Iwo Jima, and Okinawa. He relieved the Commander Fifth Amphibious Force at Okinawa in April 1945, and commanded the amphibious and support operations of that force until that island was secured at the end of June.