The occupation of Abraham (Ennugarret) Island, 31 January 1944, was the last of a series of preliminary operations that came before the invasions of Roi and Namur in Kwajalein Atoll.
Abraham was the first island to the south of Namur, and was seen as a potential artillery base.
The American plan was for the 1st Battalion, 25th Marines to capture Ivan and Jacob islands. They would then pass their amphibian tractors onto the 2nd and 3rd Battalions, which would occupy Allen and Albert Islands respectively. If there was enough time then the 3rd Battalion would move onto Abraham. The original plan was for the LVTs used to invade Albert to take place in the invasion of Abraham as well, but that news hadn’t reached the LVT commanders, and most of the surviving vehicles returned to their LSTs to refuel.
The fighting on Albert went very smoothly, and the island was secured at 1533, after only twenty minute of fighting. After the end of this fighting Colonel Chambers of the 3rd Battalion and Colonel Cumming of the 25th Marines agreed that there was still time to invade Abraham. B Hour was set at 1800. There would be no naval fire support or air support. The artillery on Albert wasn’t yet ready, so Chambers had to rely on the 60mm and 81mm mortars carried by his own troops, and some half tracks that had been attached to his unit. There were only four LVTs available, two of which were only found just before the invasion.
The water between Albert and Abraham wasn't terribly deep. Before the start of the attack the command of Company A, 4th Tank Battalion, waded almost the entire way to check the distance. A small sandspit between the two islands was easily occupied. At 1750 the mortars and half tracks began a 10 minute bombardment of Abraham, while the 81mm mortars fired smoke onto the landing beach.
At 1800 120 men from Company L, 3rd Battalion, landing on the beach. The Japanese put it a brief, almost token resistance. By 1830 two reinforced rifle companies were on the island, and by 1915 the entire island had been occupied. However, mopping up operations lasted for several more hours. Six Japanese were killed on the island, and more escaped back to Namur.
Battery B of the 4th Special Weapons Battalion and the 75mm platoon of the regimental Weapons Team took up positions on the northern end of the island, and on the following day there were five 75mm half tracks, seventeen 37mm guns, four 81mm mortars, nine 60mm mortars and sixty-one machine guns in place ready to support the fighting on Namur.