{{Short description|United States military campaign during World War II}} {{Use American English|date=April 2024}} {{Use dmy dates|date=April 2024}} {{More footnotes|date=September 2014}} {{Infobox military conflict | conflict = Mariana and Palau Islands campaign | partof = the Pacific War and World War II | image = Water Buffalo loaded with Marines.jpg | image_size = 300px | caption = A U.S. LVT loaded with Marines approaches Tinian during the U.S. landings on that island. | date = June – November 1944 | place = Mariana and Palau Islands, Pacific Ocean | result = American victory | combatant1 = {{flag|United States|1912}} | combatant2 = {{flagcountry|Empire of Japan}} | commander1 = {{unbulleted list|Chester W. Nimitz|Raymond A. Spruance|Richmond K. Turner|Holland Smith|Roy Geiger|Harry Schmidt|William H. Rupertus|Paul J. Mueller}} | commander2 = {{unbulleted list|Yoshitsugu Saitō{{Suicide|Seppuku}}<ref>Kennedy, Danger's Hour, 2009, p. 114.</ref>|Chūichi Nagumo{{Suicide}}|Jisaburō Ozawa|Kakuji Kakuta{{Suicide|Seppuku}}<ref>Yamauchi, An Asian American Ancient Historian and Biblical Scholar, 2024, Chapter 4</ref>|Takeshi Takashina{{KIA}}|Hideyoshi Obata{{Suicide|Seppuku}}<ref>Guahan, Goetzfridt, 2011, p. 502.</ref>|Kiyochi Ogata{{Suicide|Seppuku}}|Sadae Inoue|Kunio Nakagawa{{Suicide|Seppuku}}<ref>Moran, J. and Rottman, G.L., 2002, Peleliu 1944, Oxford: Osprey Publishing Ltd., {{ISBN|1841765120}}</ref>}} | strength1 = 128,000 <br/> 600+ ships | strength2 = 71,000 | casualties1 = 8,125 killed and missing<ref name="auto">{{Cite web|url=https://www.fleetoffreedom.com/mariana-palau#:~:text=The%20Allies%20secured%20the%20Palaus%20by%20November%201944,on%20Koror%20did%20not%20capitulate%20until%20August%201945.|title=Mariana & palau|website=Fleet of Freedom|access-date=26 August 2025}}</ref> | casualties2 = Over 67,000 casualties<ref name="auto"/> | campaignbox = {{Campaignbox Marianas and Palaus}} {{Campaignbox Pacific Ocean}} }} {{OSM location map| |coord={{coord|15 |135}} |nolabels = 1 |width = 280 |height = 200 |zoom=3 | title = Granite II (Mariana and Palau Islands campaign) | caption = {{legend|black|Operation Forager}}{{legend|red|Operation Stalemate}}{{legend|green|Operation Causeway (cancelled)}} |shape1=circle |shape-color1=black |mark-size1=7 |mark-coord1= {{coord|15.183333|145.75}} |label1= Saipan |label-offset-y1= -2 |mark-image1=Marines and King Kong on Saipan.jpg |mark-title1 = Battle of Saipan, 15 June–9 July 1944 |label-size1 = 9
|shape2=circle |shape-color2=black |mark-size2=7 |mark-coord2= {{coord|15|145.633333}} |label2=Tinian |label-offset-y2= 5 |mark-image2=A Water Buffalo, loaded with Marines, churns through the sea bound for beaches of Tinian Island near Guam. - NARA - 513181.tif |mark-title2 = Battle of Tinian, 24 July–1 August 1944 |label-size2 = 9
|shape3=circle |shape-color3=black |mark-size3=7 |mark-coord3= {{coord|13.5|144.8}} |label3=Guam |label-offset-y3= 6 |mark-image3=First flag on Guam - 1944.jpg |mark-title3 = Battle of Guam, 21 July–10 August 1944
|shape4=circle |shape-color4=red |mark-size4=7 |mark-coord4= {{coord|7|134.25}} |label-offset-y4= -2 |label4=Peleliu |mark-image4=First wave of LVTs moves toward the invasion beaches - Peleliu.jpg |mark-title4 = Battle of Peleliu, 15 September–27 November 1944
|shape5=circle |label5=Angaur |shape-color5=red |mark-size5=7 |mark-coord5= {{coord|6.9|134.133}} |label-offset-y5= 8 |label-offset-x5 = -2 |mark-image5=Bombardment of Anguar.jpg |mark-title5 = Battle of Angaur, 17 September–22 November 1944
|shape6=circle |shape-color6=green |mark-size6=7 |mark-coord6= {{coord|22.28|120.67}} |label6= Formosa |label-offset-y6= 8 |label-offset-x6= 2 |label-size6=11 |label-pos6=left |mark-title6 = Projected invasion of Formosa (cancelled)
|mark-size7=0 |mark-coord7= {{coord|10.83|124.83}} |label7= Leyte |label-offset-y7= 4 |mark-title7=none
|mark-size8=0 |mark-coord8= {{coord|16|121}} |label8= Luzon |label-offset-y8= 4 |mark-title8=none
|mark-size9=0 |mark-coord9= {{coord|11|114}} |label9= Philippines |label-offset-y9= |label-size9= 11 |mark-title9=none
|mark-size10=0 |mark-coord10= {{coord|12.5|138}} |label10= Philippine<br>{{spaces|3}}Sea |label-offset-y10= 8 |label-offset-x10= -30 |label-size10= 10 |shape-color10=blue |mark-image10=TBFs and SB2Cs enroute to attack during the Battle of the Philippine Sea.tif |mark-title10 = Battle of Philippine Sea, 19 June–20 June 1944
|mark-size11=0 |mark-coord11= {{coord|15|136}} |label11= Marianas |label-offset-y11= |label-size11= 11 |mark-title11=none
|mark-size12=0 |mark-coord12= {{coord|6|127}} |label12= Palaus |label-offset-y12= |label-size12 = 11 |mark-title12=none }}
The '''Mariana and Palau Islands campaign''', also known as '''Campaign Plan Granite II''', was an offensive launched by the United States against Imperial Japanese forces in the Pacific between June and November 1944 during the Pacific War.<ref>{{Cite web|url = https://www.nps.gov/parkhistory/online_books/wapa/extContent/usmc/pcn-190-003126-00/sec3.htm |title = Liberation: Marines in the Recapture of Guam (Operation in Forager)|website = www.nps.gov|access-date = 2016-03-09}}</ref> The campaign consisted of Operation Forager, which captured the Mariana Islands, and Operation Stalemate, which captured Palau. Operation Causeway, an invasion of Japanese-controlled Taiwan, was also planned but not executed.{{sfn|Operation Granite II|1944|pp=10–23}} The offensive, under the overall command of Chester W. Nimitz, followed the Gilbert and Marshall Islands campaign and was intended to neutralize Japanese bases in the central Pacific, support the Allied drive to retake the Philippines, and provide bases for a strategic bombing campaign against Japan.
The United States assembled a significant combined arms task force to undertake the campaign. The Fifth Fleet was commanded by Admiral Raymond A. Spruance. Task Force 58, commanded by Vice Admiral Marc Mitscher, consisted of 15 carriers, 7 battleships, 11 cruisers, 86 destroyers and over 900 planes. The amphibious invasion force, commanded by Vice Admiral Richmond K. Turner, consisted of 56 attack transports, 84 landing craft and over 127,000 troops.<ref>The Great Courses. ''World War II: The Pacific Theater''. Lecture 14. Professor Craig Symonds</ref>
At the beginning of the campaign, United States Marine Corps and United States Army forces, with support from the United States Navy, executed landings on Saipan in June 1944. In response, the Imperial Japanese Navy's Combined Fleet sortied to attack the U.S. Navy force supporting the landings. In the resulting Battle of the Philippine Sea (also known as the "Great Marianas Turkey Shoot") on 19–20 June, the Japanese naval forces were decisively defeated with heavy and irreplaceable losses to their carrier-borne and land-based aircraft.
Prior to the landings in the Forager invasion (Guam and Tinian) Operation Wedlock, a phantom diversion campaign was taking place. The increased radio traffic, starting in October 1943, purported a I Alaskan Corps preparing to invade the Kurile island group.<ref>{{Cite web |title=Wedlock {{!}} Operations & Codenames of WWII |url=https://codenames.info/operation/wedlock/ |access-date=2025-07-27 |website=codenames.info}}</ref> A joint army/navy radio task force was established at Adak, Alaska to push out the fake radio traffic to the equally fictitious IX Amphibious Force and 9th US Fleet.
U.S. forces landed on Saipan in June 1944 and on Guam and Tinian in July 1944. After heavy fighting, Saipan was secured in July and Guam and Tinian in August 1944. The U.S. then constructed airfields on Saipan and Tinian from which B-29s were able to conduct strategic bombing missions against the Japanese home islands until the end of World War II, including the nuclear attacks on Hiroshima and Nagasaki.
In the meantime, in order to secure the flank for U.S. forces preparing to attack Japanese forces in the Philippines, U.S. Marine and Army forces landed on the islands of Peleliu and Angaur in Palau in September 1944. After heavy fighting, both islands were finally secured by U.S. forces in November 1944, while the main Japanese garrison in the Palaus on Koror was bypassed altogether, only to surrender in August 1945 with the Japan's capitulation.
Following their landings in the Mariana and Palau Islands, Allied forces continued their ultimately successful campaign against Japan by landing in the Philippines in October 1944 and the Volcano and Ryukyu Islands beginning in January 1945.
== Operations == * Battle of Saipan, 15 June – 9 July 1944 * Battle of Guam, 21 July – 10 August 1944 * Battle of Tinian, 24 July – 1 August 1944 * Battle of Peleliu, 15 September – 27 November 1944 * Battle of Angaur, 17 September – 22 October 1944
== See also == * West Loch disaster
==References== {{Reflist}}
== Bibliography == ===Books=== *{{cite book |last=D'Albas |first=Andrieu |year=1965 |title=Death of a Navy: Japanese Naval Action in World War II |publisher=Devin-Adair Pub |isbn=0-8159-5302-X}} *{{cite book |last=Denfeld |first=D. Colt |year=1997 |title=Hold the Marianas: The Japanese Defense of the Mariana Islands |publisher=White Mane Pub |isbn=1-57249-014-4}} *{{cite book |last=Drea |first=Edward J. |year=1998 |chapter=An Allied Interpretation of the Pacific War |title=In the Service of the Emperor: Essays on the Imperial Japanese Army |publisher=University of Nebraska Press |location=Nebraska |isbn=0-8032-1708-0}} *{{cite book |last=Dull |first=Paul S. |year=1978 |title=A Battle History of the Imperial Japanese Navy, 1941–1945 |publisher=Naval Institute Press |isbn=0-87021-097-1| url-access = registration |url=https://archive.org/details/battlehistoryofi0000dull}} *{{cite book |last=Gailey |first=Harry |year=1988 |title=The Liberation of Guam 21 July–10 August |publisher=Presidio Press |location=Novato, CA |isbn=0-89141-651-X}} *{{cite book |last=Gailey |first=Harry |year=1984 |title=Peleliu: 1944 |publisher=Nautical & Aviation Pub Co of Amer |isbn=0-933852-41-X}} *{{cite book |last=Goldberg |first=Harold J. |year=2007 |title=D-day in the Pacific: The Battle of Saipan |publisher=Indiana University Press |isbn=978-0-253-34869-2}} *{{cite book |last=Hallas |first=James H. |year=1994 |title=The Devil's Anvil: The Assault on Peleliu |publisher=Praeger Publishers |isbn=0-275-94646-0}} * {{cite book |last=Hornfischer |first=James D. |author-link=James D. Hornfischer |title=The Fleet at Flood Tide: The U.S. at Total War in the Pacific, 1944–1945 |year=2016 |publisher=Random House Publishing Group |isbn=978-0345548726}} *{{cite book |last=Morison |first=Samuel Eliot |author-link=Samuel Eliot Morison |year=2001 |orig-year=1953 |edition=reissue |url=https://books.google.com/books?id=R-KfgdHvv88C |title=New Guinea and the Marianas, March 1944–August 1944 |volume=8 |series=History of United States Naval Operations in World War II |publisher=University of Illinois Press |location=Champaign |isbn=0-252-07038-0}} *{{cite book |last=O'Brien |first=Francis A. |year=2003 |title=Battling for Saipan |publisher=Presidio Press |isbn=0-89141-804-0}} *{{cite book |last=Ross |first=Bill D. |year=1991 |title=Peleliu: Tragic Triumph |publisher=Random House |isbn=0-394-56588-6| url-access = registration |url=https://archive.org/details/peleliutragictri00bill}} *{{cite book |last1=Rottman |first1=Gordon |others=illustrated by Howard Gerrard |year=2004 |title=Saipan & Tinian 1944: Piercing the Japanese Empire |publisher=Osprey Publishing |series=Campaign 137 |location=Oxford |isbn=1-84176-804-9}} *{{cite book |last2=Rottman |first2=Gordon |last1=Moran |first1=Jim |others=illustrated by Howard Gerrard |year=2002 |title=Peleliu 1944: The Forgotten Corner of Hell |publisher=Osprey Publishing |location=Oxford |series=Campaign 110 |isbn=1-84176-512-0}} *{{cite book |last=Sloan |first=Bill |year=2005 |title=Brotherhood of Heroes: The Marines at Peleliu, 1944: The Bloodiest Battle of the Pacific War |publisher=Simon & Schuster |isbn=0-7432-6009-0| url-access = registration |url=https://archive.org/details/brotherhoodofher0000sloa}} *{{cite book |last=Smith |first=Douglas V. |year=2006 |title=Carrier Battles: Command Decision in Harm's Way |publisher=U.S. Naval Institute Press |isbn=1-59114-794-8}} * {{cite book |last=Toll |first=Ian W. |author-link=Ian W. Toll |title=The Conquering Tide: War in the Pacific Islands, 1942–1944 |location=New York |publisher=W.W. Norton |date=2015}} *{{cite book |last=Wright |first=Derrick |year=2005 |title=To the Far Side of Hell: The Battle for Peleliu, 1944 |publisher=Fire Ant Books |isbn=0-8173-5281-3}}
===Reports=== *{{cite report|author=Headquarters of the Commander in Chief of the United States Pacific Fleet and Pacific Ocean Area|year=1944|title=Campaign Plan Granite II|url=https://apps.dtic.mil/sti/pdfs/ADA637709.pdf|archive-date=7 March 2024|archive-url=https://web.archive.org/web/20240307033918/https://apps.dtic.mil/sti/pdfs/ADA637709.pdf|ref={{SfnRef|Operation Granite II|1944}}}}
===Web=== *{{citation | url = https://ww2db.com/battle_spec.php?battle_id=10 | title = The Marianas and the Great Turkey Shoot | author = Chen, C. Peter | work = World War II Database | access-date = 2005-05-31}} *{{citation | last = Dyer | first = George Carroll | url = https://www.ibiblio.org/hyperwar/USN/ACTC/index.html | title = The Amphibians Came to Conquer: The Story of Admiral Richmond Kelly Turner | publisher = United States Government Printing Office | via=Hyperwar Foundation }} *{{citation |url=https://www.ibiblio.org/hyperwar/USMC/USMC-C-Saipan/index.html |date=1994 |title=Breaching the Marianas: The Battle for Saipan |series=Marines in World War II Commemorative Series |first=John C. |last=Chapin |publisher=History and Museums Division, USMC}} *{{citation | url = http://www.ibiblio.org/hyperwar/USMC/USMC-M-Saipan/index.html | title = Saipan: The Beginning of the End | author = Hoffman, Major Carl W. USMC | work = USMC Historical Monograph | publisher = Historical Branch, United States Marine Corps | year = 1950 | via=Hyperwar Foundation}} * {{cite book | url = https://history.army.mil/brochures/westpac/westpac.htm | archive-url = https://web.archive.org/web/20080103101726/http://www.history.army.mil/brochures/westpac/westpac.htm | url-status = dead | archive-date = 3 January 2008 | first = Charles R. | last = Anderson | title = Western Pacific | series = U.S. Army Campaigns of World War II | publisher = United States Army Center of Military History | year = 2003 | id = CMH Pub 72-29 | access-date = 2004-11-03}} *{{citation |last=Lodge |first=O.R. |url=https://www.ibiblio.org/hyperwar/USMC/USMC-M-Guam/index.html |title=USMC Historical Monograph: The Recapture of Guam |work=Historical Branch |publisher=United States Marine Corps |date=1954 }} *{{citation |last=O'Brien |first=Cyril J. |url=https://www.ibiblio.org/hyperwar/USMC/USMC-C-Guam/index.html |title=Liberation: Marines in the Recapture of Guam |series=Marines in World War II Commemorative Series |work=Marine Corps Historical Center |publisher=United States Marine Corps |year=1994 }} * {{citation |url=https://www.ibiblio.org/hyperwar/USMC/USMC-M-Tinian/index.html |first=Carl W. |last=Hoffman |title=USMC Historical Monograph: The Seizure of Tinian |work=Historical Branch |publisher=United States Marine Corps |date=1951 }} *{{citation | last = Chen | first = C. Peter | year = 2007 | url = http://ww2db.com/battle_spec.php?battle_id=77 | title = Palau Islands and Ulithi Islands Campaign | work = World War II Database | access-date = 2007-10-19 }} *{{cite web | last = Gayle | first = Gordon D. | year = 1996 | url = http://www.nps.gov/archive/wapa/indepth/extContent/usmc/pcn-190-003137-00/sec12.htm | archive-url = https://web.archive.org/web/20070101025159/http://www.nps.gov/archive/wapa/indepth/extContent/usmc/pcn-190-003137-00/sec12.htm | url-status = dead | archive-date = 2007-01-01 | title = Bloody Beaches: The Marines at Peleliu | work = Marines in World War II Commemorative Series | publisher = Marine Corps Historical Center | access-date = 2006-12-19 }} *{{citation | last = Hough | first = Frank O. | year = 1950 | url = http://www.ibiblio.org/hyperwar/USMC/USMC-M-Peleliu/index.html | title = The Assault on Peleliu (The Seizure of Peleliu) | work = USMC Historical Monograph | publisher = Historical Branch, G-3 Division, Headquarters, U.S. Marine Corps | access-date = 2006-12-19 |via=Hyperwar Foundation }} *{{citation | last = Smith | first = Robert Ross | year = 1996 | url = http://www.ibiblio.org/hyperwar/USA/USA-P-Approach/index.html | title = The Approach to the Philippines | work = United States Army in World War II: The War in the Pacific | publisher = United States Army Center of Military History | via=Hyperwar Foundation }} *{{citation |publisher=United States Marine Corps |work=Fleet Marine Force. G-3 Section |year=1944 |url=http://cgsc.cdmhost.com/utils/getdownloaditem/collection/p4013coll8/id/777/filename/766.pdf/mapsto/pdf/type/compoundobject/cpdtype/monograph/show/777 |title=G-3 journal : Expeditionary Troops Task Force 56 : Forager. S.l. |access-date=2016-03-08 |archive-date=30 September 2018 |archive-url=https://web.archive.org/web/20180930035853/http://cgsc.cdmhost.com/utils/getdownloaditem/collection/p4013coll8/id/777/filename/766.pdf/mapsto/pdf/type/compoundobject/cpdtype/monograph/show/777 |url-status=dead }}
== External links == {{Commons}}
{{World War II}} {{Authority control}}
{{Coord missing|Palau}}
{{DEFAULTSORT:Mariana And Palau Islands Campaign}} Category:Mariana and Palau Islands campaign Category:Battles of World War II involving the United States