Explorer Robert Cavelier de La Salle, searching for the mouth of the Mississippi River, is murdered by his own men.

René-Robert Cavelier, Sieur de La Salle (; November 22, 1643 – March 19, 1687), was a 17th-century French explorer and fur trader in North America. He explored the Great Lakes region of the United States and Canada, the Mississippi River, and the Gulf of Mexico. He is best known for an early 1682 expedition in which he canoed the lower Mississippi River from the mouth of the Illinois River to the Gulf of Mexico; there, on 9 April 1682, he claimed the Mississippi River basin for France after giving it the name La Louisiane. One source states that "he acquired for France the most fertile half of the North American continent".La Salle is often credited with being the first European to traverse the Ohio River, and sometimes the Mississippi as well. It has now been established that Joliet and Marquette preceded him on the Mississippi in their journey of 1673–74, and the existing historical evidence does not indicate that La Salle ever reached the Ohio/Allegheny Valley.