Cartier, Jacques (1491–1557), a French explorer, the discoverer of the St. Lawrence River. In 1534 he sailed from his native St. Malo on his first voyage to the New World to look for a northwest passage to Asia. He reached Newfoundland and discovered the Strait of Belle Isle. At Cape Gaspé, in the Gulf of St. Lawrence, Cartier took possession of the mainland for King Francis I. On his second voyage (1535), Cartier sailed up the St. Lawrence River to the Indian village of Hochelaga at the foot of a great hill which he named Montréal (Mount Royal). His third voyage (1541) was made to prepare the way for Roberval, first viceroy of French Canada.