Ieyasu, acting as the retired shogun, remained the effective ruler of Japan until his death. Ieyasu retired to Sunpu Castle in Sunpu, but he also supervised the building of Edo Castle, a massive construction project which lasted for the rest of Ieyasu's life. The end result was the largest castle in all of Japan, the costs for building the castle being borne by all the other daimyo, while Ieyasu reaped all the benefits. The central donjon, or tenshu, burned in the 1657 Meireki fire. Today, the Imperial Palace stands on the site of the castle.
Ogosho Ieyasu also supervised diplomatic affairs with the Netherlands and Spain. He chose to distance Japan from the Europeans starting in 1609, although the bakufu did give the Dutch exclusive trading rights and permitted them to maintain a "factory" for trading purposes. From 1605 until his death, Ieyasu consulted with an English Protestant pilot in Dutch employ, William Adams, who played a noteworthy role in forming and furthering the Shogunate's evolving relations with Spain and the Roman Catholic Church.
In 1611, Ieyasu, at the head of 50,000 men, visited Kyoto to witness the coronation of Emperor Go-Mizunoo. In Kyoto, Ieyasu ordered the remodeling of the imperial court and buildings, and forced the remaining western daimyo to sign an oath of fealty to him. In 1613, he composed the Kuge Shohatto' a document which put the court daimyo under strict supervision, leaving them as mere ceremonial figureheads. The influences of Christianity, which was beset by quarreling over the Protestant Reformation and its aftermath, on Japan were proving problematic for Ieyasu. In 1614, he signed the Christian Expulsion Edict which banned Christianity, expelled all Christians and foreigners, and banned Christians from practicing their religion. As a result, many Kirishitans (early Japanese Christians) fled to either Portuguese Macau or the Spanish Philippines.
In 1615, he prepared the Buke Shohatto, a document setting out the future of the Tokugawa regime.
The climax of Ieyasu's life was the siege of Osaka-jo Castle. The last remaining threat to Ieyasu's rule was Toyotomi Hideyori, the son and rightful heir to Hideyoshi. He was now a young daimyo living in Osaka Castle. Many samurai who opposed Ieyasu rallied around Hideyori, claiming that he was the rightful ruler of Japan. Ieyasu found fault with the opening ceremony of a temple built by Hideyori; it was as if Hideyori prayed for Ieyasu's death and the ruin of the Tokugawa clan. Ieyasu ordered Toyotomi to leave Osaka Castle, but those in the castle refused and summoned samurai to gather within castle. Then the Tokugawa, with a huge army led by Ogosho Ieyasu and Shogun Hidetada, laid siege to Osaka castle in what is now known as "the Winter Siege of Osaka". Eventually, Tokugawa was able to precipitate negotiations and an armistice after directed cannonfire threatened Hideyori's mother, Yodogimi. However, once the treaty was agreed, Tokugawa filled Osaka Castle's outer moats with sand so his troops could walk across. Through this ploy, Tokugawa gained a huge tract of land through negotiation and deception that he could not through siege and combat. Ieyasu returned to Sumpu Castle once, but after Toyotomi refused another order to leave Osaka, he and his allied army of 155,000 soldiers attacked Osaka Castle again in "the Summer Siege of Osaka." Finally in late 1615, Osaka Castle fell and nearly all the defenders were killed including Hideyori, his mother (Hideyoshi's widow, Yodogimi), and his infant son. His wife, Senhime (a granddaughter of Ieyasu), was sent back to Tokugawa alive. With the Toyotomi line finally extinguished, no threats remained to the Tokugawa clan's domination of Japan.
The end of his life
In 1616, Ieyasu died at age 73. The cause of death is thought to have been cancer or syphilis. The first Tokugawa shogun was posthumously deified with the name Tosho Daigongen, the "Great Gongen, Light of the East". (A Gongen (the prefix Dai- meaning great) is believed to be a buddha who has appeared on Earth in the shape of a kami to save sentient beings). In life, Ieyasu had expressed the wish to be deified after his death in order to protect his descendants from evil. His remains were buried at the Gongens' mausoleum at Kun¨zan, Kunozan Toshogu. After the first anniversary of his death, his remains were reburied at Nikk¨ Shrine, Nikko Toshogu. His remains are still there. The mausoleum's architectural style became known as gongen-zukuri, that is gongen-style.
Ieyasu as a person
Ieyasu had a number of qualities that enabled him to rise to power. He was both careful and bold at the right times, and at the right places. Calculating and subtle, Ieyasu switched alliances when he thought he would benefit from the change. He allied with the Hojo clan; then he joined Hideyoshi's army of conquest, which destroyed the Hojo clan; and he himself took over their lands. In this he was like other daimyo of his time. This was an era of violence, sudden death, and betrayal. He was not very well liked nor personally popular, but he was feared and he was respected for his leadership and his cunning. For example, he wisely kept his soldiers out of Hideyoshi's campaign in Korea.
He was capable of great loyalty: once he allied with Oda Nobunaga, he never went against Nobunaga; and both leaders profited from their long alliance. He was known for being loyal towards his personal friends and vassals, whom he rewarded, He was said to have a close friendship with his vassal Hattori Hanzo. However, he also remembered those who had wronged him in the past. It is said that Ieyasu executed a man who came into his power because he had insulted him when Ieyasu was young.
Ieyasu protected many former Takeda retainers from the wrath of Oda Nobunaga, who was known to harbor a bitter grudge towards the Takeda. He managed to successfully transform many of the retainers of the Takeda, Hojo, and Imagawa clans - all whom he had defeated himself or helped to defeat - into loyal followers.
After Hidetada became shogun, he married Oeyo of the Oda clan and they had two sons, Tokugawa Iemitsu and Tokugawa Tadanaga. They also had two daughters, one of whom, Sen hime, married twice. The other daughter, Kazuko hime, married Emperor Go-Mizunoo of descent from the Fujiwara clan.
Ieyasu's favorite pastime was falconry. He regarded it as excellent training for a warrior. "When you go into the country hawking, you learn to understand the military spirit and also the hard life of the lower classes. You exercise your muscles and train your limbs. You have any amount of walking and running and become quite indifferent to heat and cold, and so you are little likely to suffer from any illness.". Ieyasu swam often; even late in his life he is reported to have swum in the moat of Edo-jo Castle.
Two of his famous quotes:
"Life is like unto a long journey with a heavy burden. Let thy step be slow and steady, that thou stumble not. Persuade thyself that imperfection and inconvenience are the lot of natural mortals, and there will be no room for discontent, neither for despair. When ambitious desires arise in thy heart, recall the days of extremity thou hast passed through. Forbearance is the root of all quietness and assurance forever. Look upon the wrath of thy enemy. If thou only knowest what it is to conquer, and knowest not what it is to be defeated; woe unto thee, it will fare ill with thee. Find fault with thyself rather than with others."
"The strong manly ones in life are those who understand the meaning of the word patience. Patience means restraining one's inclinations. There are seven emotions: joy, anger, anxiety, adoration, grief, fear, and hate, and if a man does not give way to these he can be called patient. I am not as strong as I might be, but I have long known and practiced patience. And if my descendants wish to be as I am, they must study patience."
He claimed that he fought, as a warrior or a general, in 90 battles.
He was interested in various kenjutsu skills, was a patron of the Yagyu Shinkage-ryu school, and also had them as his personal sword instructors.