stylistic:style_transfer, structural:expansion, stylistic:tone, linguistic:voice_change
Ōgosho (1605–1616)

From 1605 onwards, Ieyasu, retired from official position as Shogun and now become a retired shōgun (大御所, ōgosho), 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 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. Edo became the center of political power and the de facto capital of Japan, although the historic capital of Kyoto remained the de jure capital as the seat of the emperor. Furthermore, Ieyasu had the Imperial Court appoint his eldest remaining son, Hidetada, as Shogun, announcing to the world that the position of Shogun would be hereditary to the Tokugawa clan from then on. At the same time, he requested Toyotomi Hideyori to meet the new Shogun, Hidetada, but Hideyori refused. In the end, the matter was resolved by sending his sixth son, Matsudaira Tadateru to Osaka Castle. At the same time, the next generation of Tokugawa clan vassals such Ii Naotaka and Itakura Shigemasa, were also appointed.

in 1608 Ieyasu has Takatora assigned the control of Tsu It was reported that the landholdings which Takatora received in Iga province were previously belongs to a lord named Tsutsui Sadatsugu, which Ieyasu stripped off and give the rights to Takatora. The initial pretext were because Sadatsugu's sloppy governance of the domain. However, historians arguing that the reason were because Sadatsugu behaved suspiciously visiting Toyotomi Hideyori at Osaka Castle, without the Shogunate approval, while the land which Sadatsugu occupied was considered as important military strategic location. Furthermore, it was more though that in Ieyasu perspective to strip the land and give it to the Todo clan as political strategy against the Toyotomi clan, as despite his patronage to the Toyotomi family, Tōdō Takatora were considered as a close ally of Ieyasu. Thus by making him to control the portions of Iga province, it could pushed more strategic locations to the influence of Shogunate without directly provoking the Toyotomi faction in Osaka.

In 1611 (Keicho 16), Ieyasu, at the head of 50,000 men, visited Kyoto to witness the enthronement 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. Furthermore, On April 12, Ieyasu presented three articles of legislation to the Daimyo lords in Kyoto. The important point of these three articles was that they referred to the Shogun's legal code since Minamoto no Yoritomo, and that they would strictly abide by the laws issued by the Shogunate from then on. Next, they made the lords swear not to conceal those who disobeyed the Shogun's orders, and not to hid or give shelters to any enemy of the states. 22 daimyo from the Hokuriku region and Western provinces agreed to the three articles of legislation and submitted an oath. daimyo lords from of Oshu and Kanto were not included in this list, because they were engaged in the construction of Edo Castle and did not come to Kyoto. In January of the following year, 11 major feudal lords from Oshu and Kanto swore to the Three Laws. After that, 50 small and medium-sized fudai and tozama feudal lords also swore to the Three Laws, and Ieyasu succeeded in making all the feudal lords in the country his vassals. Ieyasu did not have Hideyori work on national construction, nor did he have him swear to the Three Laws. However, Watanabe Daimon saw this three law articles issued by Ieyasu was a maneuver to isolate Hideyori politically by making other influential daimyo lords obey him.

In 1613, he composed the Kuge shohatto (公家諸法度), a document which put the court daimyo under strict supervision, leaving them as mere ceremonial figureheads.

In 1615, Ieyasu prepared the Buke shohatto (武家諸法度), a document setting out the future of the Tokugawa regime.