Battle of Iwo Jima order of battle

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." 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.

Naval forces
United States Pacific Fleet

Admiral Chester W. Nimitz HQ at Pearl Harbor
 * United States Fifth Fleet
 * 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

Ground forces
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):
 * US 5th Marine Division SSI.svg 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:
 * 28th_Marines.JPG 28th Marine Regiment
 * 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:
 * 27th_Marines.JPG 27th Marine Regiment
 * 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:
 * 26th_Marines_insignia.png 26th Marine Regiment
 * 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_Marines.jpg 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):
 * USMC_-_4th_Division.png 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:
 * USMC_-_23rd_Marine_Regiment.png 23rd Marine Regiment
 * 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:
 * USMC_-_4th_Division_25th_Regiment.png 25th Marine Regiment
 * 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:
 * 24thMarinesCrest.png 24th Marine Regiment
 * 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_Marines_logo.png 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:
 * US_3d_Marine_Division_SSI.svg 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:
 * Emblem_of_the_United_States_Marine_Corps.svg 21st Marine Regiment
 * 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:
 * 9THMARINES.svg 9th Marine Regiment
 * 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_Marines_logo.jpg 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 
 * 147RegimentCOA.jpg 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:
 * 3rd_Marine_Regimental_Crest.jpg 3rd Marine Regiment
 * Colonel James A. Stuart

Japan
Lieut. General Tadamichi Kuribayashi, commanding

Colonel Tadashi Takaishi, chief of staff

21,060 total men under arms

Army
 * 109th Division
 * 145th Infantry Regiment
 * 17th Mixed Infantry Regiment
 * 26th Tank Regiment
 * 2nd Mixed Brigade

Navy
 * 125th Anti-Aircraft Defense Unit
 * 132nd Anti-Aircraft Defense Unit
 * 141st Anti-Aircraft Defense Unit
 * 149th Anti-Aircraft Defense Unit