Dejima (Japanese: 出島; lit. 'exit island') or Deshima, in the 17th century also called Tsukishima (築島; lit. 'built island'), was an artificial island off Nagasaki, Japan, that served as a trading post for the Portuguese (1570–1639) and subsequently the Dutch (1641–1858). For 220 years, it was the central conduit for foreign trade and cultural exchange with Japan during the isolationist Edo period (1600–1869), and the only Japanese territory open to Westerners.
Dejima was created in 1636 by digging a canal through a small peninsula and linking it to the mainland with a small bridge. The island was constructed by the Tokugawa shogunate, whose isolationist policies sought to preserve the existing sociopolitical order by forbidding outsiders from entering Japan while prohibiting most Japanese from leaving. Dejima housed European merchants and separated them from Japanese society while still facilitating lucrative trade with the West.