This is the order of battle of the ground forces deployed for Operation Flintlock, a phase of the Pacific Theatre of World War II. Flintlock consisted of simultaneous landings by men of the United States Marine Corps and United States Army at Majuro Atoll and Kwajalein Atoll, both located in the Marshall Islands in the Central Pacific, on 31 January 1944.
Forces of Imperial Japan held several sites in the Marshalls. Majuro Atoll was targeted by US planners because it would provide an excellent fleet anchorage;Morison, pp. 228-229 its capture was the responsibility of the 2nd Battalion (reinf.) of the US Army's 106th Infantry Regiment plus a reconnaissance company of Marines.Rottman, p. 91 Because the Japanese had abandoned it over a year earlier, the atoll was declared secure at 0950 hours on D-Day.Morison, p. 227 The Japanese command considered Kwajalein Atoll, unlike Majuro, to be vital to the defense of the Marshalls. and had heavily fortified both of its major islands. Kwajalein is shaped roughly like a boomerang. Capture of the connected islands of Roi-Namur, located in the northeast corner of the atoll, was the responsibility of the 4th Marine Division.Rottman, p. 26 Roi was declared secure at 1802 hours on D+1,Rottman, p. 50 Namur at 1418 hours on D+2.Rottman, p. 53 Kwajalein Island is located at the south corner of the atoll; its capture was assigned to the US Army's 7th Infantry Division.Rottman, p. 26 The island was declared secure at 1618 hours on D+4.Rottman, p. 66 Eniwetok Atoll, being the furthest to the northwest, lay astride the air supply route for the Japanese, making it another objective for US planners.Rottman, p. 9 It was captured as the result of Operation Catchpole in February.
Four other atolls held by the Japanese in the Marshalls (Wotje, Maloelap, Mili and Jaluit) all contained a seaplane base, an airfield or both. These sites were simply bypassed as part of the US "island-hopping" strategy.Morison, p. 206
Naval command
The roles of Commander in Chief, Pacific Ocean Areas (CINCPOA) and Commander in Chief, U.S. Pacific Fleet (CINCPAC), were both exercised by Admiral Chester W. Nimitz from his headquarters at Pearl Harbor, Hawaii.Morison, p. 343
Since the Marshalls lie in the Central Pacific, their capture was the responsibility of the U.S. Fifth Fleet, led by Vice Admiral Raymond A. Spruance from aboard his flagship, heavy cruiser .Morison, p. 343
The ships and troops of Operations Flintlock were under direct operational command of Rear Admiral Richmond Kelly Turner aboard amphibious command ship .Morison, p. 343
Since the Japanese Combined Fleet had stripped most of its air power to defend the base at Rabaul, Admiral Mineichi Koga chose not to challenge the American operations in the Marshalls.Morison, p. 223
Ground troops V Amphibious Corps (Lieut. Gen. Holland M. Smith), USMC Roi-Namur Islands 4th Marine Division (Maj. Gen. Harry Schmidt, USMC) 24,902 officers and enlistedRottman, p. 27 Kwajalein Island 7th Infantry Division (Maj. Gen. Charles H. Corlett, USA) 21,768 officers and enlistedRottman, p. 28
U.S. forces
V Amphibious Corps Lieutenant General Holland M. Smith
Marine Corps (Northern Kwajalein)
4th Marine Division Major General Harry Schmidt Asst. Div. Cmdr.: Brig. Gen. James L. Underhill Chief of Staff: Col. William W. Rogers Personnel officer (D-1): Col. Merton J. Batchelder Intelligence officer (D-2): Maj. Gooderham L. McCormick Operations officer (D-3): Col. Walter W. Wensinger Logistics officer (-4): Col. William F. Brown
Nearby islands – D-Day These landings were made first to provide artillery support for the units on Roi and Namur. 25th Marine Regiment Colonel Samuel C. Cumming Exec. Ofc.: Lt. Col. Walter I. Jordan "Ivan" (Mellu), "Jacob" (Ennuebing) 1st Battalion (Lt. Col. Clarence J. O'Donnell) "Allen" (Ennubirr) 2nd Battalion (Lt. Col. Lewis C. Hudson Jr.) "Abraham" (Ennugarret), "Albert" (Ennumennet) 3rd Battalion (Lt. Col. Justice M. Chambers)
Roi (Red Beaches 2 & 3) – D+1 23rd Marine Regiment Colonel Louis R. Jones Exec. Ofc.: Lt. Col. John R. Lanigan 1st Battalion (Lt. Col. Hewin O. Hammond) 2nd Battalion (Lt. Col. Edward J. Dillon) CMoH recipient: PFC Richard B. Anderson () 3rd Battalion (Lt. Col. John J. Cosgrove Jr)
Namur (Green Beaches 1 & 2) – D+1 24th Marine Regiment Colonel Franklin A. Hart Exec. Ofc.: Lt. Col. Homer L. Litzenberg Jr. 1st Battalion (Lt. Col. Aquilla J. Dyess ( — CMoH recipient), then Maj. Maynard C. Schultz) 2nd Battalion (Lt. Col. Francis H. Brink) 2nd Battalion (Lt. Col. Austin B. Brunelli) CMoH recipients: 1st Lt. John V. Power (), Pvt. Richard K. Sorenson
14th Marine Regiment (Artillery) Colonel Louis G. DeHaven Exec. Ofc.: Lt. Col. Randall M. Victory These landings were made on D-Day to provide artillery support for the units on Roi and Namur. "Allen" (Ennubirr) 1st Battalion (Lt. Col. Harry J. Zimmer) "Albert" (Ennumennet) 2nd Battalion (Lt. Col. George B. Wilson Jr.) "Jacob" (Ennuebing) 3rd Battalion (Lt. Col. Robert E. MacFarlane) "Ivan" (Mellu) 4th Battalion (Maj. Carl A. Youngdale)
20th Marine Regiment (Engineer) Colonel Lucian W. Burnham Exec. Ofc.: Lt. Col. Nelson K. Brown 1st Battalion (Maj. Richard G. Ruby) 2nd Battalion (Lt. Col. Otto Lessing) 3rd Battalion (Lt. Cmdr. William O. Byrne)
Division troops 1st Armored Amphibian Battalion (Maj. Louis Metzger) 4th Amphibian Tractor Battalion (Lt. Col. Clovis C. Coffman) 10th Amphibian Tractor Battalion (Maj. Victor J. Croizat) 4th Tank Battalion (Maj. Richard K. Schmidt) 15th Defense Battalion (Lt. Col. Francis B. Loomis Jr.)
Army (Southern Kwajalein)
7th Infantry ("Bayonet") Division Major General Charles H. Corlett Infantry Kwajalein Isl., Left Sector (Red Beach 1) – D+2 184th Infantry Regiment Kwajalein Isl., Right Sector (Red Beach 2) – D+2 32nd Infantry Regiment Ebeye Island (Reserve regt.) – D+3 17th Infantry Regiment
Artillery 48th, 49th, 57th FA Battalions (105mm) 31st FA Battalion (155mm) Division troops 7th Reconnaissance Troop (Mechanized) 13th Engineer Combat Battalion 7th Medical Battalion 7th Counterintelligence Corps Detachment
Japanese forces
Fourth Fleet (Headquarters at Truk) Vice Admiral Masami Kobayashi On Roi-Namur Approx. 4,100 IJN personnel, 933 IJARottman, p. 31 61st Guard Force (det.) 4th Fleet Construction Unit (det.) 24th Air Flotilla HQ Rear Admiral Michiyuki Yamada () On Kwajalein Island Approx. 3,000 IJN personnelRottman, p. 31 6th Base Force 6th Submarine Base Force Rear Admiral Akiyama Monzō ()Rottman, p. 59 6th Communications Unit Yokusuka 4th SNLF (one company) 3rd Mobile Bttn. / 1st Amphib. Brigade (one company) 952nd Air Unit
Notes
References
Bibliography