On 29 February 1944, General Douglas MacArthur led Operation Brewer to take the islands from the Japanese who had occupied them beginning in 1942.
This US Naval Advance Base served as a staging area for further World War II operations in New Guinea and the Philippines.
[1] USS Mount Hood exploded accidentally while moored in Seeadler Harbor on 10 November 1944.
[2] A Japanese Mitsubishi A6M reconnaissance aircraft reported "two large aircraft carriers" at Seeadler Harbor on 22 April 1945, which were actually the U.S. Navy's Large Auxiliary Floating Dry Docks USS ABSD-2 and USS ABSD-4.
[3] The wrecks of the sections of large auxiliary floating drydock USS ABSD-4 and an Imperial Japanese ship amongst others are located within the harbor.