|René Robert Cavelier, Sieur de La Salle, explorer, was born in St. Herbland parish, Rouen, France, on November 22, 1643, the son of Catherine Geeset and Jean Cavelier. Cavelier was a wealthy wholesale merchant and “Master of the Brotherhood of Notre-Dame.” There were two other sons, the Abbé Jean Cavelier and Nicolas Cavelier, a lawyer, who died rather young, and a daughter, who married Nicolas Crevel.
The title La Salle, which René Robert assumed, was the name of a family estate near Rouen. La Salle, educated at the Jesuit College in Rouen, later entered the Society of Jesus as a novice, an act requiring him to give up his inheritance. Finding himself unsuited for priestly life, he left the the order at age twenty-two. With only a small allowance from his family, he sailed in 1666 for Canada, where his brother Jean, a priest of St. Sulpice, had gone the previous year. The Sulpicians granted him land near La Chine rapids, above Montreal, where he began a fortified village, acquired a substantial interest in the fur trade, and sought to learn Indian languages.
His imagination was fired by reports of a great river system, which he thought must flow into the Gulf of California and provide passage to China. La Salle sold his holdings in 1669 and undertook his first major exploration. The desertion of his followers forced him to turn back short of the Mississippi, leaving that discovery to the Joliet-Marquette expedition of 1673.
On trips to France in 1674 and 1677, La Salle received a patent of nobility and a seigneurial grant that included the Fort Frontenac site (Kingston, Ontario), then a trade concession to the western country. He built and launched the first sailing vessel to ply the Great Lakes, then began in earnest to carry out his plan of establishing a chain of trading posts across the Illinois country and down the Mississippi. Convinced by this time that the Mississippi emptied into the Gulf of Mexico and not the South Sea (the Pacific Ocean), he envisioned a warm-water port-fortified against Spanish and English incursion-on the Gulf to serve his commercial empire.
La Salle devoted the next three years to laying the cornerstones of his visionary plan. Consolidating Indian alliances, he built an entrepôt at Niagara and a fort among the Illinois. In the winter of 1682 he sledded down the frozen Illinois River to the Mississippi and, after the river was free of ice, descended it by canoe to reach the mouth of the eastern passes on April 7, 1682. Claiming for France all the lands drained by the river, La Salle named the territory La Louisiane in honor of the French King, Louis XIV.