During the Seven Years' War, the British captured and occupied the islands until the 1763 Treaty of Paris. During that time, Pointe-à-Pitre became a major harbour, and markets in Britain's North American colonies were opened to Guadeloupean sugar, which was traded for foodstuffs and timber. The economy expanded quickly, creating vast wealth for the French colonists. So prosperous was Guadeloupe at the time that, under the 1763 Treaty of Paris, France forfeited its Canadian colonies in exchange for the return of Guadeloupe. Coffee planting began in the late 1720s, also worked by slaves and, by 1775, cocoa had become a major export product as well.