Shogunal Regency (1651-1663)
Tokugawa Iemitsu died in early 1651, at the age of forty seven. After his death, the Tokugawa dynasty was at major risk. Ietsuna, the heir, was only ten years old. Nonetheless, despite his age, Minamoto no Ietsuna became shogun in Kei'an 4 (1651). Until he came of age, five regents were to rule in his place; but Shogun Ietsuna nevertheless assumed a role as formal head of the bakufu bureaucracy.
In this period, regents exercised power in the shogun's name. These were Sakai Tadakatsu, Sakai Tadakiyo, Inaba Masanori, Matsudaira Nobutsuna (a distant member of the Tokugawa), and one other. In addition to this regency, Iemitsu handpicked his half-brother, Hoshina Masayuki.
The first thing that Shogun Ietsuna and the regency had to address was the ronin (masterless samurai). During the reign of Shogun Iemitsu, two samurai, Yui Shosetsu and Marubashi Chuya, had been planning an uprising in which the city of Edo would be burned to the ground and, amidst the confusion, Edo Castle would be raided and the shogun, other members of the Tokugawa and high officials would be executed. Similar occurrences would happen in Kyoto and Osaka. Shosetsu was himself of humble birth and he saw Toyotomi Hideyoshi as his idol.
Nonetheless, the plan was discovered after the death of Iemitsu, and Ietsuna's regents were brutal in suppressing the rebellion, which came to be known as the Keian Uprising or the "Tosa Conspiracy". Chuya was brutally executed along with his family and Shosetsu's family. Shosetsu choose to commit seppuku rather than being captured.
In 1652, about 800 ronin led a small disturbance on Sado Island, and this was also brutally suppressed. But for the most part, the remainder of Ietsuna's rule was not disturbed anymore by the ronin as the government became more civilian oriented.
In Meireki 3 (1657), on the 18th-19th day of the 1st month, when Shogun Ietsuna was almost 20 years old, a great fire erupted in Edo and burned the city to the ground. It took two years to rebuild the city and bakufu officials supervised the rebuilding of the city. In 1659, Shogun Ietsuna presided over the opening ceremonies.
Read more about this topic: Tokugawa Ietsuna