Genna
Genna was a Japanese era name coming after Keichō and before Kan'ei. This period spanned the years from July 1615 to February 1624. The reigning emperor was Emperor Go-Mizunoo of Japan. It is also known as Genwa.
Change of era
1615 Genna gannen: The era name was changed to mark the enthronement of Go-Mizunuoo and because of disasters such as the siege of Osaka, or more commonly, siege of Osaka. 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, ending in that clan's destruction. Divided into two stages, 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 Siege of Osaka because the era name was changed from Keichō to Genna immediately following its ultimate resolution.
By order of Tokugawa Ieyasu, the era name of Emperor Xianzong of Tang China was adopted.
Events of the ''Genna'' era
1615 : 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 : Ieyasu pulled down Hōkoku-jinja.September 20, 1615 : Ieyasu promulgated the Genna-rei in 17 clauses.June 1, 1616 : Ieyasu died at Suruga.September 25, 1617 : Former-Emperor Go-Yōzei died. He is buried at Nikkō.1618 : A comet appeared in the sky.July 5, 1620 : The emperor was married to Tokugawa Kazuko, the daughter of Shōgun Hidetada; and also in that year.1620 : There were severe fires in Mikayo on the 30th day of the 2nd month and on the 4th day of the 3rd month.September 10, 1622 : the Great Genna Martyrdom — 55 foreign and Japanese Catholics are executed in Nagasaki, part of the persecution of Christians in Japan by Tokugawa Hidetada.September 6, 1623 : the bakufu raised the Imperial maintenance allowance by 10,000 koku.1623 : Tokugawa Iemitsu, son of Hidetada, came to the court of the emperor where he was made Shōgun.