On June 1, 1616, Tokugawa Ieyasu (徳川家康) died at Sunpu Castle — present-day Shizuoka City — at the age of 73. He had been born on January 31, 1543, into a minor lord's family in Mikawa Province, spent years of his childhood as a hostage passed between rival warlords, and emerged from the bloodiest century in Japanese history as the man who ended it. His death was not the end of something; it was the final piece of an architecture he had been building for decades.

Ieyasu's life was defined above all by patience. While Oda Nobunaga (織田信長) burned through Japan with speed and terror, and Toyotomi Hideyoshi (豊臣秀吉) consolidated Nobunaga's conquests with brilliance and paranoia, Ieyasu waited. He survived Nobunaga's assassination at Honnōji in 1582. He survived as Hideyoshi's subordinate through the 1580s and 1590s. When Hideyoshi died in 1598, leaving a child heir, Ieyasu moved. At the Battle of Sekigahara in 1600, he shattered the coalition of daimyo (大名, regional lords) who opposed him and took effective control of Japan. In 1603, the emperor appointed him shogun — a title that had been held by the Minamoto, Ashikaga, and Toyotomi, but which Ieyasu intended would pass only through his own family's hands forever.

In 1605, Ieyasu resigned as shogun in favor of his son Tokugawa Hidetada (徳川秀忠), just two years after receiving the title. This was not retirement. It was a demonstration: the shogunate belonged to the Tokugawa family, not to any individual Tokugawa. No one could argue that it was Ieyasu's personal authority that made the office legitimate — it was the family's authority. Ieyasu then relocated to Sunpu Castle and continued governing the country from there for another eleven years, until his death.

In January 1616, Ieyasu traveled to Tanaka Castle in Tōtōmi Province to practice falconry, which he had pursued all his life and credited as a discipline that kept a samurai physically and mentally sharp. He fell ill shortly after the visit. The most famous version of the story — told in Japan for four hundred years — says he ate sea bream tempura at the castle and was immediately struck by severe stomach pains. Modern scholars believe the underlying cause was stomach cancer or pancreatic cancer; the tempura story, however beloved, is almost certainly a legend or at most an aggravating event for a condition that had already become critical. He returned to Sunpu Castle to recuperate and never left it again.

What he did in his final weeks was remarkable. Ieyasu gave detailed, sequential instructions for what would happen after his death. His body was to be buried at Kunōzan (久能山), a cliff-top location overlooking Suruga Bay south of Sunpu — a site that required climbing 1,159 stone steps to reach. Construction of the shrine at Kunōzan had already begun in May 1616, the month of his death. His funeral was to be held at Zōjō-ji (増上寺) temple in Edo. Memorial tablets were to go to Daiju-ji (大樹寺) temple in his home province of Okazaki. And after one year, his spirit was to be ceremonially moved to a small shrine to be built at Nikkō (日光), in the mountains north of Edo.

He requested deification as 東照大権現 (Tōshō Daigongen, "Great Gongen, Light of the East"). A 権現 (gongen) is a Shinto deity manifested in the form of a buddha — a syncretic concept that blended Japan's two great religious traditions into a single divine identity. Ieyasu was not asking to be remembered as a great man. He was asking to be worshipped as a protective deity of Japan and of his dynasty. Every shogun who came after him would govern under the literal divine protection of his deified founder.

His son Hidetada oversaw the construction of both the Kunōzan and Nikkō shrines. The great shrine at Nikkō Tōshō-gū (日光東照宮) — completed in 1617 and massively expanded in 1636 — became one of the architectural wonders of Japan. Its Yōmeimon (陽明門) gate is covered in more than 400 carved figures of animals, flowers, and mythological beings; tradition holds that one carving was left deliberately incomplete, because a perfect object invites the wrath of the gods. The shrine is a UNESCO World Heritage Site and receives over a million visitors annually.

Ieyasu's death on June 1, 1616, closed something as well as beginning something. The Sengoku era (戦国時代) — the century of civil war in which samurai had lived by constant battle, treachery, and sudden death — was over. The man patient enough to survive it all, and careful enough to design a peace that would outlast him by 268 years, was gone. The dynasty he left behind governed Japan until 1868.