Louis-Joseph Gaultier de La Vérendrye (November 9, 1717 – November 15, 1760) was a French Canadianfur trader and explorer. He, his three brothers, and his father Pierre La Vérendrye pushed trade and exploration west from the Great Lakes. He, his brother, and two colleagues are thought to be the first Europeans to have crossed the northern Great Plains and seen the Rocky Mountains in Wyoming.