1615Genna gannen (元和元年): The era name was changed to mark the enthronement of Go-Mizunuoo and because of disasters such as the Siege of Osaka (大坂の役,,Ōsaka-no-eki), or more commonly -- Siege of Osaka (大坂の陣,,Ōsaka-no-jin). The old era ended and a new one commenced in Keichō 20.
The Siege of Osaka was a series of battles undertaken by the Tokugawa shogunate against the Toyotomi clan, and ending in that clan's destruction. Divided into two stages (the "Winter Campaign" and the "Summer Campaign"), and lasting from 1614 through 1615, the siege put an end to the last major armed opposition to the establishment of an enduring Tokugawa shogunate. The end of this period of fighting is also sometimes called the Genna Armistice (元和偃武,,Genna-enbu) because the era name was changed from Keichō to Genna immediately following its ultimate resolution.
1615 (Genna 1): Tokugawa Ieyasu and his son, Shōgun Hidetada, marched again to Osaka Castle, which was captured and burned; but Hideyori managed to flee to Satsuma where he had prepared a refuge in advance.
September 1, 1615 (Genna 1, 9th day of the 7th month): Ieyasu pulled down Hōkoku-jinja.
September 20, 1615 (Genna 1, 28th day of the 7th month): Ieyasu promulgated the Genna-rei in 17 clauses.
June 1, 1616 (Genna 2, 17th day of the 4th month): Ieyasu died at Suruga.