On February 19, 1945, men of the United States Marine Corps invaded the island of Iwo Jima, part of the Volcano Islands chain, in the North Pacific. This invasion, known as Operation Detachment, was a phase of the Pacific Theatre of World War II. The American goal was to establish multiple airfields that would allow escort fighters to accompany long-range bombers in their attacks on the Japanese home islands, as well as providing a place for damaged bombers to land on the return flight.
The Japanese military was determined to inflict a casualty rate so high that the U.S. government would give up its demand that Japan surrender unconditionally. To this end, the island had been covered with an extremely extensive system of fortifications and fields of fire. The United States Navy subjected the island to an unprecedented bombardment and, according to historian Samuel Eliot Morison, "In no previous operation in the Pacific had naval gunfire support been so effective as at Iwo Jima."[1] Nonetheless, Japanese artillery and machine-gun fire were extremely effective because the underground bunkers were so strong, only a direct hit by a bomb or naval shell could knock one out. Since direct hits were very difficult on well-camouflaged bunkers, many survived and inflicted a huge casualty rate on the Marines.
For the conquest of Iwo Jima, the Marine Corps assigned three divisions, a total of almost 70,000 troops, in stark contrast to the single division tasked with capturing Guadalcanal in August 1942. The conquest of Iwo Jima took five weeks, far beyond the American estimates.
United States Pacific Fleet
Admiral Chester W. Nimitz HQ at Pearl Harbor
Admiral Raymond A. Spruance in heavy cruiser Indianapolis
Joint Expeditionary Force (Task Force 51)
Vice Admiral Richmond Kelly Turner in amphibious command ship Eldorado
Amphibious Support Force (Task Force 52)
Rear Admiral William H.P. Blandy in amphibious command ship Estes
Attack Force (Task Force 53)
Rear Admiral Harry W. Hill in amphibious command ship Auburn
Expeditionary Troops (Task Force 56)
Lieutenant General Holland M. "Howlin' Mad" Smith
Chief of Staff: Col. Dudley S. Brown
Personnel officer (G-1): Col. Russell N. Jordahl
Intelligence officer (G-2): Col. Edmond J. Buckley
Operations officer (G-3): Col. Kenneth H. Weir
Logistics officer (G-4): Col. George R. Rowan
V Amphibious Corps
Major General Harry Schmidt
Chief of Staff: Brig. Gen. William W. Rogers
Personnel officer (G-1): Col. David A. Stafford
Intelligence officer (G-2): Col. Thomas R. Yancey
Operations officer (G-3): Col. Edward A. Craig
Logistics officer (G-4): Col. William F. Brown
8th Marine Field Depot (shore party command): Col. Leland S. Swindler
Landing Force Air Support Control Unit 1: Col. Vernon E. Megee
62nd Seabees
Left landing area (Green and Red Beaches):
5th Marine Division (25,884 officers and enlisted)
Major General Keller E. Rockey
Asst. Div. Cmdr.: Brig. Gen. Leo D. Hermle
Chief of Staff: Col. Ray A. Robinson
CO HQ Battalion: Maj. John Ayrault, Jr.
Personnel officer (G-1): Col. John W. Beckett
Intelligence officer (G-2): Lt. Col. George A. Roll
Operations officer (G-3): Col. James F. Shaw, Jr.
Logistics officer (G-4): Col. Earl S. Piper
Plans officer (G-5): Lt. Col. Frederick H. Dowsett
Green Beach:
Colonel Harry B. "Harry the Horse" Liversedge
Exec. Ofc.: Lt. Col. Robert H. Williams
1st Battalion (Lt. Col. Jackson B. Butterfield)
2nd Battalion (Lt. Col. Chandler W. Johnson (KIA 2 Mar), Maj. Thomas B. Pearce, Jr.)
3rd Battalion (Lt. Col. Charles E. Shepard, Jr. (to 14 Mar), Maj. Tolson A. Smoak (to 25 Mar), Lt. Col. Shepard)
Red Beaches 1 & 2:
Colonel Thomas A. Wornham
Exec. Ofc.: Col. Louis C. Plain (WIA 19 Feb), Lt. Col. James P. Berkeley)
1st Battalion (Lt. Col. John A. Butler (KIA 5 Mar), Lt. Col. Justin C. Duryea (WIA 9 Mar), Lt. Col. William H. Tumbleston (WIA 14 Mar)
2nd Battalion (Maj. John W. Antonelli (WIA 9 Mar), Maj. Gerald F. Russell)
3rd Battalion (Lt. Col. Donn J. Robertson)
Reserve:
Colonel Chester B. Graham
Exec. Ofc.: Col. Lester S. Hamel
1st Battalion (Lt. Col. Daniel C. Pollock (WIA 19 Mar), Maj. Albert V.K. Gary)
2nd Battalion (Lt. Col. Joseph P. Sayers (WIA 23 Feb), Maj. Amadeo Rea)
3rd Battalion (Lt. Col. Tom M. Trotti (KIA 22 Feb), Maj. Richard Fagan)
13th Marine Regiment (Artillery)
Colonel James D. Waller
1st Battalion (Lt. Col. John S. Oldfield)
2nd Battalion (Maj. Carl W. Hjerpe)
3rd Battalion (Lt. Col. Henry T. Waller)
4th Battalion (Maj. James F. Coady)
Service troops
Colonel Benjamin W. Gaily
3rd Amphibian Tractor Battalion (Lt. Col. Sylvester L. Stephan)
11th Amphibian Tractor Battalion (Lt. Col. Albert J. Roose)
5th Engineer Battalion (Lt. Col. Clifford H. Shuey)
5th Medical Battalion (Lt. Cmdr. William W. Ayres, USN)
5th Motor Transport Battalion (Maj. Arthur F. Torgler, Jr.)
5th Pioneer Battalion (Maj. Robert S. Riddell)
5th Service Battalion (Maj. Francis P. Daly (KIA 22 Feb), Maj. Gardelle Lewis (from 26 Feb))
5th Tank Battalion (Lt. Col. William R. Collins)
Right landing area (Yellow and Blue beaches):
4th Marine Division (24,452 officers and enlisted)
Major General Clifton B. Cates
Asst. Div. Cmdr.: Brig. Gen. Franklin A. Hart
Chief of Staff: Col. Merton J. Batchelder
CO HQ Battalion: Col. Bertrand T. Fay
Personnel officer (G-1): Col. Orin H. Wheeler
Intelligence officer (G-2): Lt. Col. Gooderham L. McCormick
Operations officer (G-3): Col. Edwin A. Pollock
Logistics officer (G-4): Col. Matthew C. Horner
Yellow Beaches 1 & 2:
Colonel Walter W. Wensinger
Exec. Ofc.: Lt. Col. Edward J. Dillon
1st Battalion (Lt. Col. Ralph Haas (KIA 20 Feb), Lt. Col. Louis B. Blissard)
2nd Battalion (Maj. Robert H. Davidson)
3rd Battalion (Maj. James S. Scales)
Blue Beach 1:
Colonel John R. Lanigan
Exec. Ofc.: Lt. Col. Clarence J. O'Donnell
1st Battalion (Lt. Col. Hollis U. Mustain (KIA 21 Feb), Maj. Fenton J. Mee)
2nd Battalion (Lt. Col. Lewis C. Hudson, Jr. (WIA 20 Feb), Lt. Col. James Taul)
3rd Battalion (Lt. Col. Justice M. Chambers (WIA 22 Feb), Capt. James C. Headley)
Reserve:
Colonel Walter I. Jordan
Exec. Ofc.: Lt. Col. Austin R. Brunelli
1st Battalion (Maj. Paul S. Treitel (to 8 Mar), Lt. Col. Austin R. Brunelli)
2nd Battalion (Lt. Col. Richard Rothwell)
14th Marine Regiment (Artillery)
Colonel Louis O. DeHaven
Exec. Ofc.: Lt. Col. Randall M. Victory
1st Battalion (Maj. John B. Edgar, Jr.)
2nd Battalion (Maj. Clifford B. Drake)
3rd Battalion (Lt. Col. Robert E. MacFarlane,)
4th Battalion (Lt. Col. Carl A. Youngdale)
Service troops
Lt. Colonel Melvin L. Krulewitch
5th Amphibian Tractor Battalion (Maj. George L. Shead)
10th Amphibian Tractor Battalion (Maj. Victor J. Croizat)
4th Engineer Battalion (Lt. Col. Nelson K. Brown)
4th Medical Battalion (Cmdr. Reuben L. Sharp, USN)
4th Motor Transport Battalion (Lt. Col. Ralph L. Schiesswohl)
4th Pioneer Battalion (Lt. Col. Richard G. Ruby)
4th Service Battalion (Lt. Col. John F. Fondahl)
4th Tank Battalion (Lt. Col. Richard K. Schmidt)
Floating reserve:
3rd Marine Division (19,597 officers and enlisted)
Major General Graves B. Erskine
Asst. Div. Cmdr.: Brig. Gen. William A. Worton
Chief of Staff: Col. Robert E. Hogaboom
CO HQ Battalion: Lt. Col. Jack F. Warner (to 14 Mar), Lt. Col. Carey A. Randall
Personnel officer (G-1): Maj. Irving R. Kriendler
Intelligence officer (G-2): Lt. Col. Howard J. Turton
Operations officer (G-3): Col. Arthur H. Butler
Logistics officer (G-4): Col. James D. Hittle
Committed to center sector D+2, attached to 4th Marine Division:
Colonel Hartnoll J. Withers
Exec. Ofc.: Lt. Col. Eustace R. Smoak
1st Battalion (Lt. Col. Marlowe C. Williams (WIA 22 Feb), Maj. Clay M. Murray (WIA 22 Feb), Maj. Robert H. Houser)
2nd Battalion (Lt. Col. Lowell E. English (WIA 2 Mar), Maj. George A. Percy)
3rd Battalion (Lt. Col. Wendell H. Duplantis)
Committed D+6:
Colonel Howard N. Kenyon
Exec. Ofc.: Lt. Col. Paul W. Russell
1st Battalion (Lt. Col. Carey A. Randall (to 6 Mar), Maj. William T. Glass (to 14 Mar), Lt. Col. Jack F. Warner)
2nd Battalion (Lt. Col. Robert E. Cushman, Jr.)
3rd Battalion (Lt. Col. Harold C. Boehm)
12th Marine Regiment (Artillery)
Lieutenant Colonel Raymond F. Crist Jr.
Exec. Ofc.: Lt. Col. Bernard H. Kirk
1st Battalion (Maj. George B. Thomas)
2nd Battalion (Lt. Col. William T. Fairbourn)
3rd Battalion (Lt. Col. Alpha L. Bowser, Jr.)
4th Battalion (Maj. Joe B. Wallen (to 20 Mar), Lt. Col. Thomas R. Belzer)
Arrived on March 20 and attached to 3rd Marine Division[2]
147th Infantry Regiment (Ohio Army National Guard)
Colonel Robert F. Johnson
Exec. Ofc.: Lt. Col. Eustace R. Smoak
1st Battalion
2nd Battalion
3rd Battalion
Service troops
Colonel James O. Brauer (to 6 Mar), Colonel Lewis A. Hohn
3rd Engineer Battalion (Lt. Col. Nelson K. Brown)
3rd Medical Battalion (Cmdr. Reuben L. Sharp, USN)
3rd Motor Transport Battalion (Lt. Col. Ralph L. Schiesswohl)
3rd Pioneer Battalion (Lt. Col. Richard G. Ruby)
3rd Tank Battalion (Lt. Col. Richard K. Schmidt)
Never landed:
Colonel James A. Stuart
Lieut. General Tadamichi Kuribayashi, commanding
Colonel Tadashi Takaishi, chief of staff
21,060 total men under arms
Army
145th Infantry Regiment
17th Mixed Infantry Regiment
26th Tank Regiment
2nd Mixed BrigadeNavy
125th Anti-Aircraft Defense Unit
132nd Anti-Aircraft Defense Unit
141st Anti-Aircraft Defense Unit
149th Anti-Aircraft Defense Unit
Orders of battle involving United States Marine forces in the Pacific Theatre of World War II: