IJN Yamato was the lead ship of the Yamato-class of the Imperial Japanese Navy, the largest battleships ever built. She was unlucky to have gone to sea after independent battleship operations, without adequate aircraft escort, became completely obsolete. Yamato did fight, with little effect, in the Battle of Leyte Gulf in October 1944, and then was sunk during an essentially symbolic mission to protect Navy honor, Operation TEN-GO, in April 1945.The last mission was triggered, indirectly, by a conversation between Emperor Hirohito and senior naval personnel, who perceived that the Emperor was criticizing lack of effort by the Navy. Multiple sources indicate that the following was said to Vice Admiral Seiichi Ito, commanding Second Fleet, who would lead the final and futile mission, but there are some differences on who was involved in the Imperial conversatgion and the formation of the TEN-GO order.
...we want you to die. Sooner or later, it will come to a special attack by the entire nation, the hundred million of them. We want you to die admirably as a model for the nation.
Battle of Leyte Gulf
- See also: Action off Samar
In the individual actions of Leyte Gulf, Yamato first fought in the Battle of the Sibuyan Sea, which was between a Japanese surface force and U.S. carrier aircraft. Her sister ship, IJN Musashi, was sunk in that battle, and the only Japanese success was shooting down fewer than 20 aircraft. Early in the morning of the 24th, U.S. search aircraft spotted IJN Yamato, near the southern cape of Mindonoro, entering Tablas Strait, and presumably intending to break into San Bernadino Strait. The U.S. assumed San Bernadino Strait was mined in patterns known only to the Japanese, and Nimitz had told Halsey that no Third Fleet ships should enter that strait without his permission. The alternative, therefore, was air strikes against Kurita.Admiral Matome Ugaki commanding the battleship division, wrote in his diary
This is like losing a part of myself. Musashi, however, was the substitute victim for Yamato. Today it was Musashi's day of misfortune, but tomorrow it will be Yamato's turn. Sooner or later both of thes ships were destined to come under concentrated enemy attack. My sorrow over Musashi's loss knows no end, but when one conducts an unreasonable battle, such losses are inevitable. Should Yamato tomorrow meet with the same fate as Musashi, I will still have Nagato but there will no longer be a unit and my existence as division commander will be meaningless. As I had already made up my mind that Yamato should be my place of death, I firmly resolve to share the fate of the ship.
Later, in the Action off Samar, she and other vessels had an opportunity to break through and devastate the transports supporting troops who had invaded at Leyte. When the U.S. destroyers made a second torpedo attack against the heavy forces, USS Heermann had been farthest from the Japanese, but was able to participate in the second torpedo attack, ordered at 0742 and executed at 0750. She launched on Haguro, which replied with gunfire. Both missed. Heermann then spotted Kongo, which was followed by the other three battleships. She fired remaining torpedoes and peppered Kongo with gunfire, then returned to the carrier formation. While Heermann did not make any hits, U.S. torpedoes from Heermann and others caught IJN Yamato between two groups of torpedoes. Yamato concentrated on avoiding the torpedoes and failed to maneuver in a manner that kept her as part of the fight.
A task force centered around Yamato, essentially the remnants of Second Fleet, was formed in April 1945. 
- Denis Warner, Peggy Warner, Sadao Seno (1984), Chapter 12, the Tide at Sunset, The Sacred Warriors: Japan's Suicide Legions, Avon, ISBN 0380676788, p. 199
- Willis Lee (14 December 1944), Report of Operations of Task Force THIRTY-FOUR During the Period 6 October 1944 to 3 December 1944., U.S. Navy
- Richardson, p. 151
- Dan Muir, Order of Battle, Final Sortie of the Imperial Japanese Navy,(Operation TEN-GO), 7 April 1945