Battle of Leyte - Background

Background

The Philippines were an important source of supplies, especially rubber, to Japan and also commanded the sea routes to Borneo and Sumatra by which petroleum was brought to Japan: holding on to the Philippines was vital. For the U.S., capturing the Philippines was a key strategic step in isolating Imperial Japan's military holdings in China and the Pacific theater. It was also a personal matter for MacArthur: two years previously he had left the Philippines vowing to return, and he insisted that it was a moral obligation of the U.S. to liberate it as soon as possible.

From September to early October 1944, the aircraft carriers of the U.S. 3rd Fleet under Admiral William F. Halsey carried out successful missions. During the Palau and Morotai campaigns, they destroyed some 500 enemy aircraft and 180 seagoing merchant ships. These successful actions in the Philippines, Okinawa, and Formosa indicated that an invasion of the Philippines itself was now feasible.

Leyte, one of the larger Philippine islands, has numerous deep-water approaches and sandy beaches which offered opportunities for amphibious assaults and fast resupply. The roads and lowlands extending inland from Highway 1, that ran for 40 mi (64 km) along the east coast between the Abuyog town up north to San Juanico Strait between Leyte and Samar Islands, provided avenues for tank-infantry operations, as well as a basis for airfield construction. American air forces based on Leyte could strike on enemy bases and airfields anywhere in the archipelago.

A heavily-forested north-south mountain range dominates the interior and separates two sizable valleys, or coastal plains. The larger Leyte Valley extends from the northern coast to the long eastern shore and contains most of the towns and roadways on the island. The other, Ormoc Valley, situated on the west side, was connected to Leyte Valley by a roundabout and winding road, Highway 2, which ran from Palo town on the east coast, then west and northwest through Leyte Valley to the north coast, then turned south and wound through a mountainous neck to enter northern Ormoc Valley. This continued south to the port of Ormoc City, then along the western shore to Baybay town. The road then turned east to cross the mountainous waist of the island and connected with Highway 1 on the east coast at Abuyog. Below these towns, the mountainous southern third of Leyte was mostly undeveloped. High mountain peaks over 4,400 ft (1,300 m), as well as the jagged outcroppings, ravines, and caves typical of volcanic islands offered formidable defensive opportunities. The timing late in the year of the assault would force combat troops and supporting pilots, as well as logistical units, to contend with monsoon rains.

Leyte's population of over 900,000 people—mostly farmers and fishermen—could be expected to assist an American invasion, since many residents already supported the guerrilla struggle against the Japanese in the face of harsh repression. Japanese troop strength on Leyte was estimated by U.S. intelligence at 20,000, mostly of the 16th Division under Lt. Gen. Shiro Makino.