Jōō, alternatively romanized as Jō-ō or Shōō, was a Japanese era name after Keian and before Meireki. This period spanned the years from September 1652 through April 1655. The reigning emperors were Emperor Go-Kōmyō and Emperor Go-Sai.
Change of era
1652Jōō gannen: The era name was changed to Jōō, which was to mark the death of the third shōgun, Tokugawa Iemitsu. The previous era ended and a new one commenced in Keian 5, on the 18th day of the 9th month.
The name of this new era came from the Book of the Jin: "The Xia and the Shang dynasties follow their destinies, so the House of Zhou came when it was time."
Events of the ''Jōō'' era
October 3, 1653 : A violent fire destroyed a large part of the Imperial palace and many temples which were nearby. Shortly thereafter, several girls, aged 12–14 years, were imprisoned for having started this fire and others in Heian-kyō.
August 18, 1654 : A famous priest, Ingen, arrived at Nagasaki from China. His intention was to reform the practice of Buddhism in Japan.
Within the Jōō period, Japan was implementing the Sakoku policy which adopted by Tokugawa Bakumatsu. Sakoku means closed country in Japanese. Japan was adopting this policy from 1639 to 1868. There was barely any foreign trade from other countries, with exception to Chinese and Dutch merchant. Japanese residences were strictly monitored by the Government. People were not allowed to leave the country, with consequence of death penalty. Foreigners were in the same situation, anyone who attempted to enter Japan's territory would be killed by the soldiers right away. The entire country was dictated by Tokugawa government. The Sakoku policy was adopted by the ruler for preventing invaders, and keeping their national characteristics and national religion. This policy was banned after the Edo Period. The country was re-opened to the world in 1868.