With the Marshall Islands campaign of late 1944, the Marine Corps 4th Division and the Army's 7th Infantry Division moved into Japanese territory for the first time in World War II. The islands, under Japanese control since World War I, offered U.S. forces bases for reconnaissance, combat staging and logistics. They were the next step in the Allied march to the Japanese home islands.

The Commanders
Once planners chose Kwajalein and Majuro atolls as the targets of Operation Flintlock, as the campaign was code named, forces were assigned as follows:

* Rear Admiral Richard L. Conolly commanded the Northern Task Force, responsible for landing troops under Marine Major General Harry Schmidt. These troops were from the Marine 4th Division. Their objectives were Roi and Namur islands in northern Kwajalein Atoll.

* Rear Admiral Richmond Kelly Turner commanded the Southern Task Force, responsible for landing troops under Army Major General Charles H. Corlett. These troops were from the Army's 7th Infantry Division and its attached units. Their objective was Kwajalein Island in the southern Kwajalein Atoll.

* Rear Admiral Harry W. Hill commanded the Majuro Attack Force, responsible for landing troops under Army Lieutenant Colonel Frederick B. Sheldon. The V Amphibious Corps Reconnaissance Company was assigned to pinpoint location of the enemy throughout the atoll; the Army's 2nd Battalion, 106th Infantry Regiment, 27th Division would serve as the main assault force.

D-Day
D-Day in the Marshalls was set for Jan. 31, 1944. On that day, Marines in northern Kwajalein Atoll planned to seize five islands in the vicinity of Roi-Namur, while the 7th Infantry Division hoped to capture four islets near Kwajalein Island. The Majuro Attack Force also targeted four small islands for takeover. All were tactically necessary to the main objectives, scheduled for assault Feb. 1.

Combined Navy, Marine and Army forces successfully accomplished all of these missions on D-Day.

Roi-Namur
The islands of Roi and Namur, linked by a short causeway, are so close that they counted as a single target. Roi-Namur was the primary Japanese air base in the Marshalls.  Although many ships of the Northern Task Force were combat veterans, neither the troop transport drivers nor the 4th Marine Division, newly created in August 1943, had combat experience. Additionally, participants in the assault had not been able to rehearse as a unit. This combination of factors made for confusion in the launching of the assault.  Three days of naval bombardment and air strikes preceded the 4th Marine Division to Roi-Namur. On Feb. 1, ships responsible for fire support and bombardment moved in to extremely close range, maximizing their effectiveness, killing a
significant number of defenders, and earning Conolly the nickname Close-in, along with the gratitude of the troops, who were able to come into the beaches standing up. Navy ships and pilots dropped approximately 6,000 tons of heavy explosives before the Marines landed on Roi-Namur.  Once on the beach, the troops assigned to Roi (the Marine 23rd Regimental Combat Team) advanced rapidly. The Japanese resisted strongly near the airfields runways, but by late afternoon on Feb. 1 equipment was being landed to repair the airfield
for American use. Roi was secured the same day.  Capturing Namur, the job of the Marine 24th Regimental Combat Team, proved more difficult. Over half of the assigned transport craft could not be located when it was time to launch the assault. As a result, the timing of the assault waves was off, and units went in piecemeal. Next, the leading waves were halted by tracked landing vehicles that had stopped in the water, throwing everything behind them into confusion. These problems in the water caused a mix-up on the beach. Fortunately, the enemy chose not to fight at the waters edge, so the Marines could regroup.  Once ashore, the Marines advanced rapidly; at nightfall, only the north shore of the island remained to be captured. The Marines established a defensive perimeter, which the Japanese attacked several times during the night. Fire discipline among the relatively untried troops was not good, and this, rather than the Japanese attacks, posed the greatest danger to the front line. In the morning, the Marines resumed their advance, and by early afternoon they had taken Namur.  In the seizure of Roi-Namur, Marine 4th Division casualties were 313 killed and 502 wounded. They defeated an estimated 3,563 Japanese garrison forces, taking only about 90 prisoners.

Kwajalein Island
Kwajalein Island was the primary Japanese naval base in the Marshalls.  Two factors combined to make the Feb. 1 landing on Kwajalein among the most perfectly executed of the Pacific theater.  First, the 7th Infantry Division trained superbly before it left Hawaii. Second, task force commander Turner was determined
that Navy preliminary bombardment, primarily surface, would deliver a thorough pounding to the islands defenders. Turner and his heavy cruisers, battleships and destroyers delivered throughout the engagement, as did Army artillerymen.  Four days of struggle were required to subdue the Japanese, but the veterans of Attu and Kiska succeeded. Just after 7 p.m. on the fourth day, Corlett, the Army commander, radioed Turner that the island was secure.  In the seizure of Kwajalein Island and its surrounding islets, Army casualties included 173 killed and 793 wounded in overcoming an estimated 4,823 Japanese garrison troops. Of these, most were killed in combat or committed suicide; approximately 174 were taken prisoner.

Majuro Atoll
The capture of Majuro, intended for use as an air and naval base, occurred without loss of American lives. Early intelligence reports proved erroneous; when Marines from the V Amphibious Corps Reconnaissance Company landed on Jan. 31, they found no Japanese on any of the islands slated for preliminary attack. The night of Jan. 31, a Marine platoon landed on Majuro Island itself. All but one Japanese had escaped. The 2nd Battalion, 106th Infantry Regiment did not land on Majuro until Feb. 1; then, with an influx of garrison troops, it began converting Majuro into a U.S. air and naval base.

Eniwetok
The speed with which Kwajalein Atoll fell allowed Admiral Chester W. Nimitz, Commander in Chief, Pacific Ocean Areas, to move up the timetable for the seizure of Eniwetok Atoll, code named Operation Catchpole.  Catchpole came under the overall command of Rear Admiral Harry W. Hill. The V Amphibious Corps reserve, made up of the 22nd Marine Regiment (reinforced) under Marine Colonel John T. Walker and the 106th Infantry Regiment (reinforced) under Army Colonel Russell G. Ayers, provided the ground forces.

On Feb. 18, 1944, the Marines landed on Engebi Island, supported by naval gunfire and by shore-based artillery placed the day before on three adjacent islets. Engebi, which contained the atolls airfield, was secured that day.

On Feb. 19, the 106th Infantry faced a tougher situation on Eniwetok Island, but after two days of fighting and help from the 22nd Marines 3rd Battalion, Eniwetok, too, was taken. The 22nd Marines also seized Parry on Feb. 21, closing the action in the Eniwetok Atoll.

In Operation Catchpole, Marine casualties were 254 killed, 555 wounded; Army casualties were 94 killed and 311 wounded. About 3,400 Japanese died and 66 were taken prisoner. U.S. forces bypassed four remaining Japanese bases in the Marshalls (Jaluit, Maleolap, Mille and Wotje), cutting them off from reinforcement. After the war, it was learned that of approximately 13,700 Japanese left at these bases, 7,440 died from bombing, disease or starvation.

Campaign Results
The capture of the Marshall Islands moved American reconnaissance and land-based strike aircraft within range of the both the Carolines and the Marianas, and opened new bases for the U.S. Navy. It caused the Japanese navy to evacuate Truk Island in the Carolines, which was the bastion of Japanese air and naval power in the Central Pacific.  The rapid victories in the Marshalls added momentum to the Central Pacific drive. The low number of casualties under 3,000 combined for Marines and Army shows that the lessons the Marine 2nd Division paid such a high price for at Tarawa were put to good use. Surface and air bombardment and naval gunnery improved in strength and accuracy. Tactics against heavily defended atolls changed and improved. The Marshalls assault forces had more and better transportation to the beach as well.