The Battle of Leyte Gulf, also called the “Battle for Leyte Gulf”, the “Battles for Leyte Gulf”, and formerly as the “Second Battle of the Philippine Sea”, is generally considered to be the largest naval battle of World War II and also, by some criteria, the largest naval battle in history.

It was fought in waters near the Philippine island of Leyte, from 23 October to 26 October 1944, between naval and naval-air forces of the Allies and those of the Empire of Japan. On October 20, United States troops invaded the island of Leyte as part of a strategy aimed at isolating Japan from the countries it had occupied in South East Asia, and in particular depriving its forces and industry of vital oil supplies. The Imperial Japanese Navy (IJN) mobilized nearly all of its remaining major naval vessels in an attempt to defeat the Allied invasion, but was repulsed by the US Navy’s 3rd and 7th Fleets. The IJN failed to achieve its objective, suffered very heavy losses, and never afterwards sailed to battle in comparable force. The majority of its surviving heavy ships, deprived of fuel, remained in their bases for the rest of the Pacific War.

The Battle of Leyte Gulf included four major naval battles: the Battle of the Sibuyan Sea, the Battle of Surigao Strait, the Battle of Cape Engaño and the Battle off Samar, as well as other actions.

Leyte Gulf is also notable as the first battle in which Japanese aircraft carried out organized kamikaze attacks.

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