Yamamoto Isoroku Memorial Museum Captions
Letter to Takano Kihachi, 1899
In this handwritten letter, Isoroku recounts the story of a recent school trip to his brother, Takano Kihachi, who was living in Tokyo’s Ueno district and studying to become a dentist at the time.
He talks about climbing a mountain known as “Yoneyama” with two of his fellow middle school classmates, and jokes about hiding from a giant that they encountered on their hike. The letter shows Isoroku’s command of humor and the written form, which is beyond that of an average teenager. It also shows the close bond he feels with his brother. He laments that although the trip was fun, he would rather be studying in Ueno alongside Kihachi.
Isoroku’s Birth
Isoroku was born into the Takano family, which had a long history in the Nagaoka area and were of samurai stock. Takano Eiken (1693–1773; born Takano Nagasada) and his son Yokei (1729–1815; born Tsunemichi) were two of his noted ancestors. They were both retainers of the Echigo-Nagaoka domain. His grandfathers, father, and brothers fought in the Boshin War (1868–1869). However, in addition to their military honors, the Takano family had earned a reputation over several generations for being accomplished writers of poetry and verse.
The inscription reads: “In all, life is short.” It is taken from “Greeting Meiji Year 30,” written when Isoroku was a first-year middle school student.
Benjamin Franklin’s Autobiography
When Isoroku was a middle school student, he obtained this copy of Benjamin Franklin’s autobiography. He was a great admirer of Franklin and his struggle to liberate the American people from their colonial oppressors. He wanted to follow Franklin’s example and someday become a great leader.
Isoroku’s Middle School Notebook
A further example of Isoroku’s admiration for Benjamin Franklin can be seen in this notebook from his third year of middle school, when he was 16 years old. The name Franklin is written on the notebook in Chinese characters.
Isoroku’s Birthplace
The Takano family home was originally located next to Nagaoka Castle, but it was destroyed during the Boshin War. After the war, the family built a new wooden house with a floor space of approximately 1,320 square meters. This is large by modern Japanese housing standards, but would have been relatively small for a family of their social standing.
Isoroku was born on the first floor of this new home. Later, part of the same floor would serve as his study room.
Adoption
In 1916, Isoroku was adopted into the Yamamoto family, also former samurai of Nagaoka. It was common in Japan at the time for families that did not have a male heir to adopt a young man who showed promise. Even at this early stage, the Yamamoto family could see Isoroku’s potential.
“Always on the Battlefield” Motto
Jozai senjo (have a spirit of always being on the battlefield). This was a motto of the Makino family, the lords of the Nagaoka domain for centuries up until the Meiji era (1868–1912). The first-generation Makino and his retainers established a rigorous training regimen and it was continued for centuries. It prepared warriors to defend their territory whenever necessary.
In peacetime, those who served the Makino family were encouraged to maintain good health, save money, and be battle-ready at all times. This was a philosophy that Isoroku also believed in and tried to follow in his daily life.
Worldwide Traveler
In this postcard, dated April 1926, Isoroku describes his recent travels to his brother, Kihachi. Around this time, Isoroku spent a total of nine months traveling in the Americas and Europe.
While abroad, he gained an appreciation for advanced technology and realized that air travel and oil were to become important drivers of international development in the years ahead. One line says: “I’m going to Mexico to inspect oil facilities.”
Postcards from Around the World
During his travels, Isoroku sent many postcards to members of his family and associates. These include the postcards shown here, which he sent to his former mentor Watabe Atau and his brother Kihachi.
Among other things, Isoroku tells about his English studies at Harvard University and his work at the Japanese Embassy in Washington, D.C. He also mentions his travels with Ide Kenji, an admiral, as part of the delegation negotiating the Washington Naval Treaty.
Sojourn in the United States
In May 1919, Isoroku went to the United States, where he stayed for a time in Boston. He studied English at Harvard University and augmented his lessons with extra tutoring in the evenings. In December of that year, he was promoted to the rank of lieutenant colonel of the Navy. Later, in May 1920, he started work with the Japanese Embassy in Washington, D.C. as naval attaché.
Soon, he was tasked with helping Japanese ambassador Shidehara Kijuro prepare for the upcoming International Telecommunications Conference. Isoroku long held the belief that Japan needed to modernize its technology to keep up with the United States and Europe. He saw this task as both a great honor and one of major importance to his country’s future.
When his term of office concluded in 1926, Isoroku sought to further his knowledge of the international oil business by traveling to Mexico at his own expense to observe oil field operations there.
Letter to Nishiyama Izuko (1919)
Isoroku composed this letter to Nishiyama Izuko, the 14-year-old niece of one of his hometown friends, while he was living in the United States. In the letter, he contrasts the lifestyles of the more independent-minded American women with Japanese women, who tended to prioritize maintaining the family unit over their own personal ambitions.
He encouraged Izuko to find a balance between high aspirations and the societal expectations within which she lived. He believed a harmonious home life was the key to Japan’s future prosperity, but he also believed women should be encouraged to realize their potential.
Charity and Generosity
Isoroku was a great believer in charity, and would often go out of his way to support those who were important to him. In this 1940 letter to Watabe Yokiko, his teacher’s daughter, he declares: “I will serve, honor, and reward my teacher for the 50 years he has given me.”
Playing Cards
Isoroku loved games of all kinds, from card games like bridge, to games of chance like mahjong and roulette, to other games like shogi (a Japanese variant of chess). To him, these games were more than just entertainment. They also served the crucial purpose of training his mind for battle. Playing them, he said, taught him vital lessons.
First, he believed, whether you win or lose, you must always remain calm and exercise clear judgment. Second, you must be patient, but when the opportunity arises to take down your opponent, do it swiftly and with no hesitation. Third, to win, you must balance being bold with being cautious.
However, Isoroku also reflected on the occasional need for self-sacrifice, adding: “You cannot make accurate judgments all the time if you only act in your own self-interest.”
The Quest for Peace
Yamamoto Isoroku believed it was a mistake for Japan to enter into the Tripartite Pact with Germany and Italy in 1940. He strongly opposed this action and had done all he could to keep Japan from denouncing the earlier Washington Naval Treaty. He felt that aircraft, rather than sea vessels, were the future of the nation’s military. He continued to believe Japan’s leaders should focus on upholding national security instead of engaging in aggression overseas.
Letter to Takano Kihachi (1927)
In this 1927 letter to his brother, Isoroku expresses his concerns about the many geopolitical challenges Japan is facing. He comments on the Showa financial crisis, the Japanese government’s recent cabinet reshuffle, and ongoing Japanese military operations in the Shandong region of China.
He placed great importance on the upcoming Geneva Disarmament Conference. Isoroku saw the conference as Japan’s best chance to achieve peace and quell growing tensions around the world.
Participation in the London Naval Conference
In 1930, Yamamoto Isoroku was a member of the Japanese delegation to the London Naval Conference. He is pictured here with other prominent members of the delegation: Takarabe Takeshi, Matsudaira Tsuneo, Nagai Matsuzo, Abo Kiyokazu, Sakonji Seizo, and Yamaguchi Tamon, among others.
At the conference, Isoroku worked closely with Sir Robert Craigie of the British delegation, and the two men formed a friendship. Craigie, who would later go on to become the British ambassador to Japan, spoke highly of Isoroku and his negotiating capabilities.
Second London Naval Conference
Yamamoto Isoroku wrote this 1934 letter to his brother Kihachi during the preliminary negotiations for the Second London Naval Conference. Following his impressive showing at the 1930 conference, Isoroku earned the opportunity to represent Japan again alongside the country’s ambassador to Britain, Matsudaira Tsuneo.
Once again, the tone of this letter shows how important Isoroku believed these talks were to Japan’s future. He goes to great lengths to emphasize how hard he will negotiate.
Navy Promotion and the Importance of Aircraft
Isoroku returned to Japan in early 1935 after concluding the preliminary negotiations for the Second London Naval Conference. He was promoted to director of the Japanese Naval Aviation Division and immediately set about trying to reform Japan’s military strategy. His firm belief was that “the main force in national defense is aircraft. Ships exist only to provide aid.”
He would later become Deputy Secretary of the Navy.
In 1939, Yamamoto gave an address to students at his alma mater, Nagaoka Middle School. There, he once again emphasized the importance of aircraft, expressing the hope that these students would see a more peaceful future.
Memorial for Shipmates
Isoroku always cared greatly for those under his command. This memorial book was taken from a shrine on board the aircraft carrier Akagi during his tenure as captain.
At that time, the Naval Air Force was training hard for the conflict that was to come, and some corpsmen lost their lives in accidents. Isoroku saw it as essential that his officers take time to honor their fallen comrades.
Note on 6,000 Years of History
In this written memo, Isoroku gives a quick summation of Japan’s ancient history. He recounts the legends of the gods, their connection to Japan, and their place in the modern world.
The memo shows that, as well as being progressive for his time in a scientific and cultural sense, Isoroku had great respect for the sacred, more mythical aspects of Japanese culture.
Christian Bible
As a middle school student, Isoroku was inspired by a Christian pastor named Newell, who taught him baseball. Throughout his life, Isoroku retained a keen interest in religion, reading this Bible and also studying a number of Buddhist and Shinto texts.
Staunch Opposition to a Pact with Germany
Isoroku remained firmly opposed to Japan’s pact with Germany, even in the face of personal threats and disdain from his colleagues. In this statement, written around May 31, 1939, he reiterates his belief that an alliance with Nazi Germany will bring about war with the United States and the United Kingdom, leading to Japan’s ruin. Isoroku’s time in these countries perhaps gave him insight into the mentality of their people that other Japanese leaders lacked.
Commander-in-Chief of the Combined Fleet
Having spent time in their country, Isoroku knew all too well the military power and strong will of the Americans. Nonetheless, in this letter to Watabe Shigenori, written in May 1941, he expresses the hope of achieving an early peace. He says Japan must “overcome this great torrent, and survive.”
Commanding the Battleship Nagato
At the time of its commission, the Nagato was the world’s largest battleship. It was also the first in the world to carry forty-centimeter guns. The even bigger, more famous ships Musashi and Yamato entered service years later.
Photo of the Final Meeting Before Pearl Harbor
From November 13–14, 1941, the Commander-in-Chief of the Japanese Navy Yamamoto Isoroku, his chief of staff, and most of the fleet assembled at the Iwakuni Naval Base in Yamaguchi Prefecture, in western Japan.
It was here that the plan for bombing Pearl Harbor underwent final revisions. Isoroku still hoped, up until the last possible moment, that a peace deal with the Americans could be reached. He ordered that the attack be called off, even if the attacking forces were already approaching Pearl Harbor, in the event that such a peace deal could be brokered.
Gift of Tea Cups
Yamamoto Isoroku presented this ceremonial teacup to Fujiwara Ginjiro, a businessman who was prominent in Japan before and after the war. When the war ended, Ginjiro and some other friends of Isoroku used the cup in a ceremony to honor his memory.
Portable Tea Set
This portable tea set is named “Kachidoki” (literally, “cry of victory”). Portable tea sets were created to allow enjoyment of tea in the traditional Japanese style, even on the battlefield. Each utensil in the set is selected to symbolize fortune in war, long life, and victory, as appropriate to a fighting man. After the war concluded, the Yamamoto family kept this set as a memento.
Isoroku’s Short Sword
Some ten short swords were produced under the commission of Emperor Hirohito immediately after the outbreak of the Pacific War and presented to his most trusted staff and advisers. The present short sword is one of them. It has a straight, eight-inch blade, which is rounded at the tip. It belonged to Isoroku. His eldest son, Yamamoto Yoshimasa, has donated the sword to the museum.
The forging of the short swords was done mainly by two sword makers, Ikkansai Shigemasa (1905–1995; born Sakai Hiroshi) and Endo Mitsuoki (1904–1992). This sword was made by Mitsuoki, a resident of the city of Niigata. The engraving of characters on the blade—in Isoroku’s own hand—was done by Abe Akitada (1899–1977), a resident of the city of Sanjo in Niigata Prefecture. It reads, “Kōkoku no kōhai” (The rise and fall of Imperial Japan) on the front, and, “Kakarite kono seisen ni ari” (Depends on this military expedition) on the back.
While not intended for use in battle, these short swords inspired morale among those fortunate enough to carry them.
The blade collar is made of pure silver, and also has engravings: Onshi (“imperial gift”) on the front, and Wakatsu (“presented to you”) on the back.
Letter to the Central Naval Command, November 12, 1942
On August 7, 1942, American troops took command of the island of Guadalcanal in the South Pacific, including the Japanese airfields based there. Japanese leaders believed this island was strategically important and that retaking it was vital to winning the war in the Pacific.
However, despite three valiant attempts, they could not retake the island. Isoroku was forced to pen this letter to Miwa Yoshitake, the head of the Naval Command, conceding that, despite his determined efforts, the island remained under American control.
Personal Letter to Nagino Toru
In this January 1943 letter, written just three months before his death, Isoroku speaks candidly of his growing worries and anxieties about the war, as it continues to drag on and the outlook becomes increasingly bleak for Japan. He worries about his family, his hometown, and what will become of Nagaoka when the war ends. It is one of the few examples of him using the local Nagaoka dialect in his writing.
Japan Aviation Society Journal
Throughout his life and naval career, Isoroku remained fascinated with airplanes. He believed aviation was the way of the future. What is perhaps less well-known is that he also had a deep love of geography. He was a reader of National Geographic, published in the United States, and was always striving to learn more about the wider world and its layout. Furthermore, Isoroku kept himself reliably informed of the latest aviation developments by subscribing to the journal of what was then the Japan Aviation Society.
Yonai Mitsumasa Calligraphy
Even a great power will fall if it is belligerent; if, under peace, it forgets war, it will be doomed.
This calligraphy by Yonai Mitsumasa (1880–1948) was composed as a final tribute to his friend, Yamamoto Isoroku. Yonai became Prime Minister of Japan in 1940 after serving as admiral and Navy Minister. A native of Iwate Prefecture, he was Yamamoto Isoroku’s longtime friend and political ally. Yonai’s tenure as Navy Minister overlapped with Isoroku’s tenure as Deputy Secretary of the Navy. The two combined their resources for two years and seven months from February 1937 in an attempt to prevent Japan from entering into the Tripartite Pact with Germany and Italy. But, soon after they left their posts, the pact was easily concluded.