For a long time, Nagasaki had been the entrance to Japan for foreign traders and the like. The very first (outside of Asia) were the Portuguese, who had a good deal of influence on Japan including on the language and food. But given the regligious influence and from fear of colonization, the Shogun built this small island Dejima in Nagasaki to limit the Portguese from going elsewhere in Japan. But the Portuguese left.
Then the Dutch became the dominant traders, so the Dutch ended up as the residents in Dejima for the next 200 years while Japan closed itself from the rest of the world. The Dutch paid the equivalent of US$1 million a year, and patiently stayed on.
It was very interesting and surreal to walk in the miniscule area (less than 10 minutes to walk across!) that was the only "foreign" place in Japan for such a long time.