Luzon, Battle of, was a clash of Japanese forces against United States and Filipino forces during World War II (1939-1945). The battle lasted from January to August 1945. It ended in a U.S.-Filipino victory. Luzon is the largest of the Philippine Islands, in the southwest Pacific Ocean. The American campaign to free Luzon from Japanese occupation was the largest of the Pacific war.
Background.
In December 1941, the Japanese military attacked the Philippines, which at that time was a U.S. commonwealth. The last U.S. forces on Luzon surrendered in May 1942. The Japanese treated American and Filipino prisoners harshly (see Bataan Death March ). Recovery of the Philippines became a major goal of U.S. armed forces in the Pacific. 
Beginning in late 1942, U.S. forces won a series of hard-fought victories over Japan. By October 1944, the Americans were within reach of the Philippines. That month, U.S. forces invaded the Philippine island of Leyte. In December, they took Mindoro, an island south of Luzon. American Army engineers built two airfields on Mindoro to support the planned Luzon invasion.
The plan to capture Luzon was part of Operation Victor. American Army General Douglas MacArthur commanded the U.S. invasion force of some 400,000 troops. Many thousands of Filipinos aided and fought alongside U.S. troops throughout the campaign. About 260,000 Japanese troops defended Luzon.
The battle.
On Jan. 9, 1945, U.S. Army troops landed at Lingayen Gulf on Luzon’s west coast. They faced little opposition at first. The American forces raced south toward Manila, the capital and largest city of the Philippines. In late January, more U.S. troops landed west and south of Manila. On January 30, Army Rangers and Filipino guerrilla forces freed hundreds of Allied prisoners in a daring raid on a camp at Cabanatuan.
On February 3, U.S. troops entered Manila. They soon freed thousands of Allied prisoners held at Santo Tomás University and Bilibid Prison. Heavy fighting then erupted throughout the city. Japanese defenders fought from buildings and from within Manila’s famed Intramuros, or Walled City. Combat raged for weeks, as American and Filipino forces slowly eliminated Japanese resistance. The city suffered severe damage from combat and from the demolition of buildings by retreating Japanese troops. Many thousands of Manila’s citizens died in the fighting. Japanese troops murdered thousands more. American and Filipino forces secured Manila by March 4, but the city was devastated.
During the fight for Manila, U.S. troops swept the Japanese from the nearby Bataan Peninsula and the island fortress of Corregidor. Bataan and Corregidor had played key roles in the American defense, and surrender, in 1942.
After securing Manila, American and Filipino forces attacked Japanese forces to the southeast. Brutal combat raged in the region’s rolling hills and valleys until late May 1945. American troops then cleared Japanese positions throughout Bicol, Luzon’s long southeastern peninsula. Some 150,000 Japanese troops battled American and Filipino forces in the mountains of northern Luzon for months. The fighting ceased on August 15 after Japan agreed to surrender and end the war. At that time, some 50,000 Japanese troops remained to surrender on Luzon.
Aftermath.
The capture of Luzon cost the lives of more than 8,000 U.S. troops, with over 29,000 wounded. More than 100,000 Filipinos were killed. About 200,000 Japanese troops died in the fighting. Malaria and other diseases affected thousands from both sides.
The victory at Luzon liberated numerous Allied prisoners of war and freed Filipinos from Japanese occupation. It also cut Japan’s supply route to Indonesia. The Japanese officially surrendered on September 2, bringing an end to World War II.
