The seizure of the Ogasawara archipelago and the Volcano Islands were outlined in the OCTAGON Conference in September 1944 between U.S. President Franklin D. Roosevelt , British Prime Minister Winston Churchill and the Combined Joint Chiefs of Staff . Due to General Douglas MacArthur 's landing on Leyte , it made modifications to the Combined JCS initial directive for General MacArthur to further seize Luzon on the targeted date of December 1944 and Admiral Chester Nimitz to provide cover and naval support by seizing the Bonin Islands , or the lesser Volcano Islands , on or about January 20 , 1945 and Okinawa in the Ryukyu Islands on or about March 1 , 1945 . Both the islands of Formosa and Amoy were to be bypassed due to their physical size , close proximity to Japanese air strikes and the large , substantial numbers of the Japanese Marines that were heavily fortified in the area
OCTAGON Conference
Second Quebec Conference
United States Marine Corps Amphibious Reconnaissance Battalion