This marked the beginning of Operation Flintlock, the invasion of Kwajalein. The island was seen as an important base for conducting air operations against the rest of the Marshall Islands and eventually the Marianas. The force took the lightly defended island in one day without any casualties. Battle of Kwajalein The same day as the Majuro invasion, the 4th Marine Division under Major General Harry Schmidt began their assault on Kwajalein. Schmidt's troops first landed on Roi-Namur, a group of islands in the northern part of the atoll. Major confusion and delays were caused by poor weather and American troops inexperienced in amphibious operations, but the pre-invasion naval and air bombardment was extremely effective. Out of roughly 3,000 Japanese soldiers, only about 300 were left to guard the island. On the southern island of Kwajalein, Major General Charles H. Corlett's 7th Infantry Division landed on southern Kwajalein with relative ease. Although the Japanese pillboxes, bunkers, and intense infantry offensives slowed the Americans, more troops, more experience in amphibious landings, effective pre-landing bombardment, and Japanese defenses on the opposite side of the atoll from where the Americans landed contributed to the capture of Kwajalein and its surrounding islands on 7 February. Of the entire force of about 8,000 Japanese guarding Majuro and Kwajalein, only 51 survived, and 253 were taken prisoner. The Americans suffered 348 men killed, 1,462 wounded, and 183 missing in the eight days it took to take the atoll. Battle of Eniwetok Eniwetok's islands and islets housed enough room for airfields critical for the upcoming invasion of the Marianas. Major General Yoshimi Nishida knew that it would be extremely difficult to hold the main island of Eniwetok against the invasion. He had roughly 4,000 troops, half of them Army soldiers, while the rest were a variety of Navy sailors. Since the Americans would be landing with naval and air support, therefore giving them the upper hand, he decided to stop them at the beaches. On 17 February 1944, a naval bombardment of Eniwetok Atoll began. This marked the beginning of Operation Catchpole. The same day, the 22nd Marine Regiment under Colonel John T. Walker landed on the northern island of Engebi. The landings were a logistical nightmare, with American troops, gear, and supplies scattered along the beach. Walker and his Marines took the island on 18 February with 85 dead and 166 wounded. On 19 February, the 106th