Hawaiian pizza is a pizza originating in Canada, and is traditionally topped with pineapple, tomato sauce, cheese, and either ham or bacon. Sam Panopoulos, a Greek-born Canadian, created the first Hawaiian pizza at the Satellite Restaurant in Chatham, Ontario in 1962. Inspired in part by his experience preparing Chinese dishes which commonly mix sweet and savory flavors, Panopoulos experimented with adding pineapple, ham, bacon, and other toppings.

Source: Wikipedia