Battle of Saipan order of battle

On 15 June 1944, United States Marine forces landed on the southwest coast of the island of Saipan in the central Marianas chain; these were followed a day later by US Army forces. This invasion was part of Operation Forager, an effort to recapture the entire Marianas chain from the Empire of Japan.

The island had been a Japanese possession since it was captured by the Imperial Japanese Army during World War I. As military conflict with the United States became increasingly likely during the 1930s, Japan expended great effort in fortifying Saipan. In mid-1944, nearly 30,000 troops were based on the island, almost double the estimates of US intelligence.^[1]

US forces declared Saipan secure on 9 July 1944.

United States

Naval commanders for Operation Forager

Adm. Chester W. Nimitz

Adm. Raymond A. Spruance

Vice Adm. Richmond Kelly Turner

Naval forces

United States Pacific Fleet^[2]
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 Rocky Mount

Northern Attack Force (Task Force 52 – Saipan and Tinian)

Vice Admiral Turner

Southern Attack Force (Task Force 53 – Guam)

Vice Admiral Richard L. Conolly in amphibious command ship Appalachian

Ground forces

Ground force commanders on Saipan

Lieut. Gen. Holland M. Smith

Maj. Gen. Harry Schmidt

Expeditionary Troops (Task Force 56)
Lieutenant General Holland M. "Howlin' Mad" Smith^[a]

Chief of Staff: Brig. Gen. Graves B. Erskine^[b]

Personnel Officer (G-1): Lt. Col. Albert F. Metze

Intelligence Officer (G-2): Col. St. Julien R. Marshall

Operations Officer (G-3): Col. John C. McQueen

Logistics Officer (G-4): Col. Raymond E. Knapp

Plans Officer (G-5): Col. Joseph T. Smith

Northern Troops and Landing Force (Task Group 56.1 – Tinian and Saipan)

Consisting of V Amphibious Corps

Southern Troops and Landing Force (Task Group 56.2 – Guam)

Consisting of III Amphibious Corps

V Amphibious Corps
Lieutenant General Holland M. Smith^[c]

Chief of Staff: Brig. Gen. Graves B. Erskine

XXIV Corps Artillery (Brig. Gen. Arthur M. Harper)

1st Provisional Gun Group

225th Field Artillery Howitzer Group

2nd Marine Division command on Saipan

Maj. Gen. Thomas E. Watson

Brig. Gen. Merritt A. Edson

Left beaches

2nd Marine Division (21,746 officers and enlisted)

Major General Thomas E. Watson

Asst. Div. Cmdr.: Brig. Gen. Merritt A. Edson

Red beaches

6th Marine Regiment

Commanding Officer: Col. James P. Riseley

Executive Officer: Lt. Col. Kenneth F. McLeod

1st Battalion (Lt. Col. William K. Jones)

2nd Battalion (Lt. Col. Raymond L. Murray)

3rd Battalion (Lt. Col. John W. Easley)

Green beaches

8th Marine Regiment

Commanding Officer: Col. Clarence R. Wallace

Executive Officer: Lt. Col. Jack P. Juhan

1st Battalion (Lt. Col. Lawrence C. Hays Jr.)

2nd Battalion (Lt. Col. Henry P. Crowe)

3rd Battalion (Lt. Col. John C. Miller Jr.)

Floating reserve

2nd Marine Regiment

Commanding Officer: Col. Walter J. Stuart

Executive Officer: Lt. Col. John H. Griebel

1st Battalion (Lt. Col. Wood B. Kyle)

2nd Battalion (Lt. Col. Richard C. Nutting)

3rd Battalion (Lt. Col. Arnold F. Johnston)

Landed after D-Day

10th Marine Regiment (Artillery)

Commanding Officer: Col. Raphael Griffin

Executive Officer: Lt. Col. Ralph E. Forsyth

1st Battalion (Lt. Col. Presley M. Rixey)

2nd Battalion (Lt. Col. George R. E. Shell)

3rd Battalion (Maj. William L. Crouch)

4th Battalion (Lt. Col. Kenneth A. Jorgensen)

18th Marine Regiment (Engineer)

Commanding Officer: Lt. Col. Ewart S. Laue

1st Battalion, 18th Marines (Lt. Col. August L. Vogt)

2nd Battalion, 18th Marines (Lt. Col. Chester J. Salazar)

Attached units

1st Battalion, 29th Marine Regiment (Lt. Col. Guy E. Tannyhill; Lt. Col. Rathvon M. Tompkins; Lt. Col. Jack P. Juhan)^[5]

715th Amphibian Tractor Battalion (Army)

4th Marine Division command on Saipan

Maj. Gen. Harry Schmidt

Brig. Gen. Samuel C. Cumming

Right beaches

Two Marines crawl to their assigned positions on the beach on Saipan.

4th Marine Division (21,618 officers and enlisted)

Major General Harry Schmidt

Asst. Div. Cmdr.: Brig. Gen. Samuel C. Cumming

Blue beaches

23rd Marine Regiment

Colonel Louis R. Jones

Exec. Ofc.: Lt. Col. John R. Lanigan

1st Battalion (Lt. Col. Ralph Haas)

2nd Battalion (Lt. Col. Edward J. Dillon)

3rd Battalion (Maj. John J. Cosgrove)

Yellow beaches

25th Marine Regiment

Colonel Merton J. Batchelder

Exec. Ofc.: Lt. Col. Clarence J. O'Donnell

1st Battalion (Lt. Col. Hollis U. Mustain)

2nd Battalion (Lt. Col. Lewis C. Hudson)

3rd Battalion (Lt. Col. Justice M. Chambers)

Floating reserve

24th Marine Regiment

Colonel Franklin A. Hart

Exec. Ofc.: Lt. Col. Austin R. Brunelli

1st Battalion (Lt. Col. Robert N. Fricke)

2nd Battalion (Lt. Col. Richard Rothwell)

3rd Battalion^[d] (Lt. Col. Otto Lessing)

Landed after D-Day

14th Marine Regiment (Artillery)

Colonel Louis G. DeHaven

Exec. Ofc.: Lt. Col. Randall M. Victory

1st Battalion (Lt. Col. Harry J. Zimmer)

2nd Battalion (Lt. Col. George B. Wilson Jr.)

3rd Battalion (Maj. Robert E. MacFarlane)

4th Battalion (Lt. Col. Carl A. Youngdale)

20th Marine Regiment (Engineer)

Lt. Colonel Nelson K. Brown

Exec. Ofc.: Capt. William M. Anderson

1st Battalion (Maj. Richard G. Ruby)

2nd Battalion (Maj. John H. Partridge)

Attached units

708th Amphibian Tank Battalion (Army)

773rd Amphibian Tractor Battalion (Army)

534th Amphibian Tractor Battalion (Army)

Maj. Gen. Ralph C. Smith

Expeditionary Troops reserve (Landed D+1)

27th Infantry Division (Army) (16,404 officers and enlisted)

Major General Ralph C. Smith (thru 24 Jun) ^[e]

Major General Sanderford Jarman (24 Jun thru 28 Jun)

Major General George W. Griner (after 28 Jun)

Blue beaches

Infantry

105th Infantry Regiment

106th Infantry Regiment

165th Infantry Regiment

Artillery

104th Field Artillery Battalion

105th Field Artillery Battalion

106th Field Artillery Battalion

249th Field Artillery Battalion

Armor

762nd Tank Battalion

766th Tank Battalion

Engineer

102nd Engineer Combat Battalion

502nd Engineer Combat Battalion

Navy

UDT 5

UDT 6

Japan

Commanders of Imperial forces in the Marianas and on Saipan

Vice Adm. Chūichi Nagumo

Lt. Gen. Yoshitsugu Saito

Central Pacific Area Fleet HQ^[6]
Vice Admiral Chūichi Nagumo (self-inflicted gunshot 6 July)
Chief of staff: Rear Adm. Hideo Yano (seppuku 7 July)

Thirty-first Army^[f]

Lieutenant General Hideyoshi Obata (on inspection tour of Guam during battle; seppuku there 11 August)

14th Air Fleet

Defenses of Saipan

Lieutenant General Yoshitsugu Saito (seppuku 7 July)

Approx. 25,500 army and 6,200 navy personnel

43rd Division

118th Infantry Regiment

135th Infantry Regiment

136th Infantry Regiment

Divisional support

47th Independent Mixed Brigade

316th Independent Infantry Battalion

317th Independent Infantry Battalion

318th Independent Infantry Battalion

Other units

3rd Independent Mountain Artillery Regiment

9th Tank Regiment (of 1st Tank Division)

3rd Battalion, 9th Independent Mixed Regiment

1st Battalion, 18th Infantry Regiment

25th Antiaircraft Artillery Regiment

7th Independent Engineer Battalion

14th Independent Mortar Battalion

17th Independent Mortar Battalion

Miscellaneous straggler units

Notes

^ Generated so much ill will between the armed services in the Pacific Theater that he had to be relieved of command in July 1945.^[3]
^ Commanded 3rd Marine Division on Iwo Jima.
^ Assigned to command of Fleet Marine Force, Pacific, an umbrella command of all Marine Corps forces in the Pacific Theater.^[4]
^ Pvt. Lee Marvin, later a prominent Hollywood actor, was wounded while serving in Company I of this unit during the struggle for Mount Tapochau.
^ Relieved of command and expelled from the island by Lt. Gen. Holland Smith for allowing his troops to fall behind the Marine Corps advance up the island.
^ A Japanese army was equivalent to a Euro-American corps.

References

^ Rottman, p. 42
^ Rottman, p. 35
^ Rottman, p. 31
^ Rottman, p. 28
^ Johnston, Goldberg
^ Rottman, p. 91

Bibliography

Clark, George B. (2006). The Six Marine Divisions in the Pacific: Every Campaign of World War II. Jefferson, North Carolina: McFarland and Co. ISBN 978-0-7864-2769-7.
Goldberg, Harold J. (2007). D-Day in the Pacific: The Battle of Saipan. Indiana University Press. ISBN 978-0-25334-869-2.
Johnston, Richard W. (1987). Follow Me: The Story of the Second Marine Division in World War II. Battery Press. ISBN 0-89839-099-0.
Morison, Samuel Eliot (1953). New Guinea and the Marianas, March 1944 – August 1944. History of United States Naval Operations in World War II. Vol. VIII. Boston: Little, Brown and Co. LCCN 53-7298.
Rottman, Gordon; Howard Gerrard (2004). Saipan & Tinian 1944: Piercing the Japanese Empire. Oxford: Osprey Publishing. ISBN 1-84176-804-9.

External links

[4] Generated so much ill will between the armed services in the Pacific Theater that he had to be relieved of command in July 1945.^[3]

[5] Commanded 3rd Marine Division on Iwo Jima.

[7] Assigned to command of Fleet Marine Force, Pacific, an umbrella command of all Marine Corps forces in the Pacific Theater.^[4]

[9] Pvt. Lee Marvin, later a prominent Hollywood actor, was wounded while serving in Company I of this unit during the struggle for Mount Tapochau.

[10] Relieved of command and expelled from the island by Lt. Gen. Holland Smith for allowing his troops to fall behind the Marine Corps advance up the island.

[12] A Japanese army was equivalent to a Euro-American corps.

[1] Rottman, p. 42

[2] Rottman, p. 35

[3] Rottman, p. 31

[6] Rottman, p. 28

[8] Johnston, Goldberg

[11] Rottman, p. 91

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