Dejima or Deshima, in the 17th century also called Tsukishima , was an artificial island off Nagasaki, Japan that served as a trading post for the Portuguese (1570–1639) and subsequently the Dutch (1641–1854). 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.