The invaders left their foods behind. The German missionaries left potatoes. The Japanese forced the islanders to grow rice to make sushi. The Americans introduced a diet of canned mackerel and ham, as well as Budweiser. Because of this, when I ordered sushi in Pohnpei, lovely rolls arrived, perfectly formed around tiny cubes of Spam.
NOTE: Here’s a recipe from Guam for Spam Sushi. http://www.paulaq.com/guamsushirecipe.html