Sakoku is the common name for the isolationist foreign policy of the Japanese Tokugawa shogunate under which, during the Edo period, relations and trade between Japan and other countries were severely limited, and nearly all foreign nationals were banned from entering Japan, while common Japanese people were kept from leaving the country. The policy was enacted by the shogunate government (bakufu) under Tokugawa Iemitsu through a number of edicts and policies from 1633 to 1639. The term sakoku originates from the manuscript work Sakoku-ron (鎖國論) written by Japanese astronomer and translator Shizuki Tadao in 1801. Shizuki invented the word while translating the works of the 17th-century German traveller Engelbert Kaempfer concerning Japan.

Japan is an island country in East Asia. It is in the northwest Pacific Ocean and is bordered on the west by the Sea of Japan, extending from the Sea of Okhotsk in the north toward the East China Sea, Philippine Sea, and Taiwan in the south. Japan is a part of the Ring of Fire, and spans an archipelago of 14,125 islands, with the five main islands being Hokkaido, Honshu, Shikoku, Kyushu, and Okinawa. Tokyo is the country's capital and largest city, followed by Yokohama, Osaka, Nagoya, Sapporo, Fukuoka, Kobe, and Kyoto.