The Sakoku Edict (Sakoku-rei, 鎖国令) of 1635 was a Japanese decree intended to eliminate foreign influence, enforced by strict government rules and regulations to impose these ideas.
Tokugawa Ieyasu, who conquered Japan in 1600, was skeptical of the Spanish and Portuguese, due in part to the influence of his English advisor William Adams.
Ieyasu's successor Hidetada significantly curtailed Catholic activity in Japan and banned foreign trading in Osaka and Kyoto.
The allowance of ships was strictly regulated; only specific vessels were permitted to enter Japan, and merchants had to obtain special licenses to trade.
This isolationist policy would continue to thrive until 1854, over two hundred years later, when Commodore Matthew Perry from the Americas compelled Japan at the Convention of Kanagawa (Nichibei Washin Jōyaku, 日米和親条約).
The signing of this document opened numerous trade ports in areas such as Edo, Kobe, Nagasaki, Niigata and Yokohama along Japan’s coast.