La Salle La Salle, Ren'e-Robert Cavalier, Si eur de (1643-1687), French explorer in North America, who navigated the length of the Mississippi River and claimed the Louisiana region for France. La Salle was born on November 22, 1643, in Rouen, France, and educated by the Jesuits. In 1666 he immigrated to Canada, was granted land on the St. Lawrence River, and became a trader. From 1669 to 1670 he explored the region south of Lakes Ontario and Erie, and he later claimed to have discovered the Ohio River in 1671. In the course of his explorations in the wilderness, La Salle became familiar with indigenous languages and traditions.

Because of his capabilities, French colonial governor Louis deBuade, comte de Pal luau et de Frontenac, appointed him commander of Fort Frontenac, then being built as a trading station. In 1674 La Salle was sent to France as Frontenac's representative to justify the building of the fort. His mission was successful, and he received a patent of nobility. La Salle subsequently conceived a plan for exploring and trading farther west, and in 1677 he again visited France to secure royal approval of his scheme. He returned with Italian explorer Henri de Tony, who became his associate. In 1679 he set out on a preliminary expedition, and after establishing forts at the mouth of the Saint Joseph River and along the Illinois River, in February 1680, he sent a group to explore the upper Mississippi River.

La Salle then returned to Fort Frontenac to procure new supplies and funds. By spring he was able to travel west again, and he andTonty proceeded with their party of French and indigenous peoples to the Mississippi, which they descended to the Gulf of Mexico in 1682, claiming all the land drained by the river for Louis XIV, king of France, and naming the region Louisiana. La Salle subsequently commenced construction of forts in the new territory. When Frontenac was recalled to France later in 1682, however, La Salle's rivals succeeded in turning the new governor against him. Journeying to France in 1683, La Salle made a successful appeal to the king, who commended him for his discoveries and named him viceroy of North America. In 1684 he sailed from France with a fleet of four ships on an expedition to establish a colony at the mouth of the Mississippi River.

When he reached the Gulf of Mexico he was unable to find the Mississippi, and landed on the shore of what is now Matagorda Bay, Texas, believing the bay to be the western outlet of the Mississippi. After several fruitless searches by land for the mouth of the river, La Salle realized his mistake. In January 1687 La Salle set out for Canada with a party of 17 men to procure help for the few members left of the original expedition. His men mutinied, however, and he was killed near the Trinity River. One of LaSalle's supply ships, the Belle, sank in 1686 during a storm and was discovered in Matagorda Bay in 1995.