The Marianas archipelago consists of fifteen volcanic islands located 3,300 miles west of Hawaii and 1,500 miles east of the Japan or the Philippines. In the summer of 1944 the Mariana Islands, a vital Japanese station on their internal lines of shipping and communication, became the next vital step in the U.S. war against Japan. Continuing the advance in the Central Pacific by Admiral Chester Nimitz' naval forces made the Marianas the next stop on the path to Tokyo. Bases in the Marianas would put U.S. Army Air Corps B-29 bombers within range of the Japanese home islands for the first time.
Map of the Western Pacific showing strategic location of the Marianas.
Today in WW II: 20 Jun 1943 Operation TOENAILS opens with Marines landing at Segi Point on Vangunu Island, southeast of New Georgia.
Background to the Invasion of the Marianas
To seize the Marianas, in June 1944 American forces executed Operation Forager, a joint operation involving ground units of U.S. Marines and U.S. Army, supported by naval gunfire and air support, with the objective of the capture of Saipan, Tinian, and Guam, the main islands of the Marianas. The Japanese attempt to interdict the invasion with a decisive attack on the U.S. Fifth Fleet in the Battle of the Philippine Sea resulted in a disastrous loss of Japanese planes and pilots without impeding the invasion.
The Invasions of Saipan, Guam, and Tinian
Marines wade ashore on Tinian from landing barges, blocked by reefs. Unlike the barges, the LVT amphibious tractors in the assault wave made it to the beach and were used as tanks on the island.
Each of the major islands of the Marianas was invaded and captured in turn:
Importance of the Marianas Campaign
The American victory in the Marianas was the first combined operation executed by Army, Navy, Marine Corps, and Army Air Force units. The success set the pattern for the further development of joint operations in the Central and Southwest Pacific. The loss of the Marianas and the crippling of Japanese sea power in the Battle of the Philippine Sea, eliminated any possibility of a Japanese recovery and resurgence. With the Marianas in American control, Japan's sea lines of communication were cut off from natural resources and their own military forces in Southeast Asia. Soon B-29 Superfortress bombers based in the Marianas began to pound the Japanese home islands as U.S. forces closed the ring ever tighter on Japan.
Recommended Books about the Invasion of the Marianas
Find More Information on the Internet
There are many fine websites that have additional information on this
topic, too many to list here and too many to keep up with as they come and go.
Use this Google web search form to get an up to date report of what's out there.
For good results, try entering this: 1944 saipan guam tinian. Then click the Search button.