The main U.S. advance toward Munda, entrusted to the 43rd Division, started on 5 July from Zanana Beach five miles east of the airfield. It immediately stalled in the face of fierce Japanese resistance, a shortage of supplies, poor leadership and inexperience, forbidding terrain, and jungle conditions. As the advance sputtered, the 37th Infantry Division and units from the 25th Infantry Division were committed, and Major General Oscar W. Griswold, commander of the XIV Corps, replaced Hester as commander of the NGOF. Griswold later replaced Hester as commander of the 43rd Division with Major General John Hodge.
Meanwhile, the Allied landings sparked a series of naval battles off New Georgia. On the morning of 6 July in the Battle of Kula Gulf, a U.S. Navy task force intercepted a Japanese squadron bringing reinforcements and supplies to New Georgia Island. The Americans lost a light cruiser while sinking two Japanese destroyers. A week later, in the Battle of Kolambangara, U.S. and Japanese task forces again tangled in an engagement in which the Japanese lost a light cruiser and the Americans a destroyer, and in the Battle of Vella Gulf on 6–7 August, a U.S. Navy task force of six destroyers smashed a Japanese squadron of four destroyers transporting 900 men and supplies to New Georgia. The Americans sank three of the Japanese destroyers, resulting in the deaths of some 1,000 Japanese. Thereafter, the Japanese gave up any hope of expelling the Americans from the island group.
Griswold launched a major offensive against Munda on 25 July supported by massive air, artillery, and naval bombardment. Initially, the Americans gained little ground, but after days of brutal close-in fighting, Griswold's men slowly pushed the outnumbered Japanese from their positions. On 5 August, following Noboru's decision to pull back because of heavy casualties, the 43rd Division captured Munda Airfield. During the next weeks, despite an aggressive pursuit, most of the remaining Japanese defenders escaped to nearby islands. In September, the Americans seized Baanga, Arundel, and Vella Lavella Islands. In early October, the campaign came to an end when the Japanese evacuated 9,000 defenders of Kolombangara Island to Bougainville Island 100 miles to the north.
The New Georgia operation provided the Allies with several good airfields and brought them closer to Rabaul. U.S. losses were 1,094 dead and 3,873 wounded, as well as several thousand casualties from disease and battle fatigue. Japanese losses are not known, although the XIV Corps reported 2,483 Japanese dead exclusive of those on Vella Lavella.
John Kennedy Ohl
Altobello, Brian J. Into the Shadows Follow: The Brutal Battle for New Georgia. Novato, CA: Presidio Press, 2000.; Hammel, Eric. Munda Trail: Turning the Tide against the Japanese in the South Pacific. New York: Orion Books, 1989.; Miller, John, Jr. Cartwheel: The Reduction of Rabaul. Washington, DC: Office of the Chief of Military History, Department of the Army, 1959.; Morison, Samuel Eliot. History of United States Naval Operations in World War II. Vol. 5, The Struggle for Guadalcanal, August 1942–February 1943. Boston: Little, Brown, 1949.