On October 20, 1944, the U.S. Sixth Army, supported by naval and air bombardment, landed on the favorable eastern shore of Leyte, one of the islands of the Visayas island group, northeast of Mindanao.
The Japanese miscalculated the relative strength of the naval and air forces, and they attempted to destroy the landing.
This brought about the massive sequence of battles called the Battle of Leyte Gulf, fought on October 23 through October 26.
This decisive victory by the U.S. Navy, its Fast Carrier Task Force, its surface fleet, and its submarines effectively destroyed the remainder of the Imperial Japanese Navy (IJN), which had already lost all of its effective aircraft carrier forces.
The IJN had four of its carriers sunk (ships with depleted air squadrons – which were used only as decoys), numerous battleships and heavy cruisers, and a large number of light cruisers and destroyers.
The IJN was never able to fight a major battle after this.

The U.S. Sixth Army continued its advance from the east, as the Japanese rushed reinforcements to the Ormoc Bay area on the western side of the island.
While the Sixth Army was continually reinforced, the U.S. Fifth Air Force and the U.S. 3rd Fleet's Task Force 38 were able to devastate the Japanese attempts at air attacks and at landing new reinforcements and supplies, and also provide much support to the Army's ground troops during what is known as the Battle of Ormoc Bay from November 11 to December 21, 1944.

The Filipino guerrillas also performed valuable service in maintaining public order and in keeping the roads and highways free of congestion.
After the American beachheads were established, the Leyte guerrilla groups were attached directly to the Sixth Army corps and divisions to assist in scouting, intelligence, and combat operations.

With the initial U.S. Sixth Army landings on the beaches at Tacloban and Dulag, Colonel Ruperto Kangleon's units went into action.
They dynamited key bridges to block Japanese displacement toward the target area; they harassed enemy patrols; and they sabotaged supply and ammunition depots.
Information on enemy troop movements and dispositions sent from guerrilla outposts to Kangleon's Headquarters was dispatched immediately to Sixth Army.

During many torrential rains and over difficult terrain, the advance continued across Leyte and onto the major island of Samar, just north of Leyte.
On December 7, 1944, the U.S. Army units made another amphibious landing at Ormoc Bay and, after a major land and air battle, the landing force cut off all Japanese ability to reinforce and resupply their troops on Leyte.
Although fierce fighting continued on Leyte for months, the U.S. Army was always in control.
On October 20, 1944, the U.S. Sixth Army, supported by naval and air bombardment, landed on the favorable eastern shore of Leyte, one of the islands of the Visayas island group, northeast of Mindanao. The Japanese miscalculated the relative strength of the naval and air forces, and they attempted to destroy the landing. This brought about the massive sequence of battles called the Battle of Leyte Gulf, fought on October 23 through October 26. This decisive victory by the U.S. Navy, its Fast Carrier Task Force, its surface fleet, and its submarines effectively destroyed the remainder of the Imperial Japanese Navy (IJN), which had already lost all of its effective aircraft carrier forces. The IJN had four of its carriers sunk (ships with depleted air squadrons – which were used only as decoys), numerous battleships and heavy cruisers, and a large number of light cruisers and destroyers. The IJN was never able to fight a major battle after this.
The U.S. Sixth Army continued its advance from the east, as the Japanese rushed reinforcements to the Ormoc Bay area on the western side of the island. While the Sixth Army was continually reinforced, the U.S. Fifth Air Force and the U.S. 3rd Fleet's Task Force 38 were able to devastate the Japanese attempts at air attacks and at landing new reinforcements and supplies, and also provide much support to the Army's ground troops during what is known as the Battle of Ormoc Bay from November 11 to December 21, 1944.
The Filipino guerrillas also performed valuable service in maintaining public order and in keeping the roads and highways free of congestion. After the American beachheads were established, the Leyte guerrilla groups were attached directly to the Sixth Army corps and divisions to assist in scouting, intelligence, and combat operations.
With the initial U.S. Sixth Army landings on the beaches at Tacloban and Dulag, Colonel Ruperto Kangleon's units went into action. They dynamited key bridges to block Japanese displacement toward the target area; they harassed enemy patrols; and they sabotaged supply and ammunition depots. Information on enemy troop movements and dispositions sent from guerrilla outposts to Kangleon's Headquarters was dispatched immediately to Sixth Army.
During many torrential rains and over difficult terrain, the advance continued across Leyte and onto the major island of Samar, just north of Leyte. On December 7, 1944, the U.S. Army units made another amphibious landing at Ormoc Bay and, after a major land and air battle, the landing force cut off all Japanese ability to reinforce and resupply their troops on Leyte. Although fierce fighting continued on Leyte for months, the U.S. Army was always in control.
Philippines campaign (1944–1945)