An adopted child, Isoroku Yamamoto graduated from Japan's Imperial naval academy in 1904 at age 20. He was assigned to a cruiser, and in May 1905 he participated in the big naval battle of Tsushima Strait, where the new Japanese Navy defeated the Russian Navy. Yamamoto was wounded in the left hand and leg and lost two fingers, but recovered and continued with his naval career.
In 1919, Yamamoto was sent to learn in the United States. He studied English in Harvard University, and also learned about the United States, and became familiar with its strengths and weaknesses better than other Japanese officers who never visited in America.
After graduating from Harvard in 1921, he returned to Japan and specialized in the new field of military aviation, and particularly naval aviation.
In 1926, already a senior officer, he returned to the United States for two more years, this time as the Japanese naval attache in Washington. In this role he became familiar with the U.S Navy. His opinion of the U.S Navy was low, and he described it as a club of golfers and bridge players. However, after spending four years in America, Yamamoto was fully aware of the power of the United States as a nation.
In 1930 Yamamoto was an Admiral and represented Japan in the conference of naval powers in London. Later that year Yamamoto was assigned to a senior role in the naval aviation headquarters, where he continued to be a driving force in the development of Japan's aircraft carriers force and in making it the Navy's spearhead, focusing on enhancing the quality of its aircraft and tactics. In an era when carrier-launched fighters were inferior to land-based fighters, Yamamoto's demands led to the development of Japan's excellent carrier-launched fighter, the Zero, and other excellent aircraft. The Japanese Navy was equipped with the world's fastest, most powerful and most efficient torpedoes, and with the best air-dropped torpedoes.
In 1933 he returned to the sea as the commander of an aircraft carriers group, but in 1935 his fast promotion returned him to Tokyo to become vice minister of the Navy, a non-political role in Japan's militarist regime. In this senior role he kept advancing the idea that the aircraft carrier took the place of the battleship as the main type of warship, an idea which many Admirals, who served on battleships, found hard to accept. It was so in other navies too, and changed only when the aircraft carriers proved their advantage over the battleship in the naval battles of World War 2. Yamamoto said that in modern warfare, the battleships will be like the samurai sword, a mighty weapon of the past which now became useless. He described the ability of the small aircraft to defeat the huge battleship as a swarm of ants overcoming a snake.
Despite his great contribution to making the Japanese Navy one of the most modern and powerful navies in the world, he strongly and consistently opposed those in the militarist Japan who wanted to go to war. But in the late 1930s Japan was so extremely militarist that it resulted in 1939 in a plot to murder Yamamoto. To protect him from being assassinated by the extremists in Tokyo, Yamamoto was sent back to the ocean. The minister of the Navy promoted him to full Admiral and made him the commander of The Combined Fleet, a mighty Armada which practically included the entire force of the Japanese Navy. While the Navy headquarters and ministry were in charge of all the staff affairs, Admiral Isoroku Yamamoto was to lead Japan's entire Navy in battle, an Admiral's dream job.
Before he left, Yamamoto was asked by prime minister Konoe about Japan's chances in a war against the United States and Great Britain. His answer was "We can run wild for six months or a year, but after that I have utterly no confidence. I hope you will try to avoid war with America". His prophecy was later proved correct. In October 1941, General Hideki Tojo, the aggressive minister of war, became the new prime minister, and Japan went to the war. As commander of The Combined Fleet, Admiral Yamamoto knew that the best thing for Japan in such a war was to destroy the US Pacific Fleet in a long range preemptive attack by carriers aircraft at its main base in Pearl Harbor. Yamamoto planned a daring attack on Pearl Harbor, and there were worries about it, but eventually his plan was approved.
A year before, in November 1940, a single British aircraft carrier launched 21 obsolete torpedo bombers to a surprise attack against the Italian Navy harbor in Taranto in the Mediterranean. They sank 3 battleships for the loss of just two aircraft, and the next day the remaining Italian vessels escaped from Taranto to more distant harbors. This successful example helped convince the skeptics and approve Yamamoto's daring plan. Compared with the British raid in Taranto, Yamamoto's plan was in a much greater scale, using a much greater force against a much greater target and to a tremendous range of 3400 miles, but with much better aircraft and weapons, highly trained aviators, and the advantage of total surprise.
The attack at Pearl Harbor was a great success, and with the successes that followed, Yamamoto became a national hero in Japan. Yamamoto's next plan intended to complete his achievement in Pearl Harbor by attracting the remaining units of the US Pacific Fleet, particularly its aircraft carriers, to a decisive battle. Again there was initial opposition to his plan, but after American bombers launched from an aircraft carrier bombed Tokyo, the Doolittle Raid, his new plan was approved.
In June 4, 1942, six months after his victory in Pearl Harbor, Yamamoto led the Combined Fleet to a decisive battle near the island of Midway, in the center of the Pacific. Yamamoto lost in the Battle of Midway for two main reasons. One reason was that the US naval intelligence knew in advance of his plan to attack Midway and could respond in a way which surprised the Japanese. The other reason was that while Yamamoto himself was an expert in using aircraft and aircraft carriers, his aircraft carriers task force was commanded by Admiral Nagumo, a torpedo specialist. This was not a major problem in the previous battles where things went as planned, although Nagumo was criticized for not launching an additional attack wave in Pearl Harbor. But in the battle of Midway the Japanese Navy was surprised, and since the aircraft carriers force sailed ahead of the main fleet, Yamamoto was not there to quickly override Admiral Nagumo's orders. In a short but destructive battle of air strikes between the American and Japanese aircraft carriers, Nagumo lost his four aircraft carriers, Japan's best carriers, with all their aircraft and elite air crews, for the loss of one American carrier. In Midway, Japan lost its initiative in the Pacific war, it was exactly as Yamamoto predicted before the war.
Admiral Yamamoto kept fighting against the US Navy for ten more months, when in April 1943, in another intelligence success, US Navy Intelligence decoded a Japanese radio message which informed that Yamamoto intends to visit his units in the northern Solomon islands on April 18, 1943.
Even after Midway, America regarded Admiral Yamamoto as its most formidable enemy in the war against Japan, and this intelligence provided a unique opportunity to assassinate him. Worried of possible political implications, Admiral Nimitz, commander of the US Pacific Fleet, asked Washington if he may do it, and the answer was yes.
The 339th fighter squadron of the US army Air Force, equipped with long range P-38 Lightning fighters, was informed of Yamamoto's itinerary and was ordered to intercept his aircraft. The meeting point was far in Japanese controlled air space, so 16 Lightnings were sent to intercept Yamamoto along his flight path. They arrived and loitered at low altitude for a while when they saw their target, two G4M Betty bombers escorted by six Zero fighters. The American fighters focused on the bombers and shot down both of them and one of the Zeroes over the jungle.
Admiral Isoroku Yamamoto, the planner of the attack in Pearl Harbor, was killed. Japan was shocked by the loss of its best Admiral. Yamamoto's successor said "We had only one Yamamoto and no one can replace him". Admiral Yamamoto received the highest state honors in his funeral. He was also posthumously promoted to the highest rank of Fleet Admiral, and Germany, Japan's ally, honored him too as the only foreigner awarded the Knight's Cross with oak leaves and swords, one of its highest medals, awarded to Germany's most outstanding aces and military leaders.
The Battle of Midway