Verendrye brothers' journey to the Rocky Mountains

The Vérendrye brothers were the first Europeans to cross the northern Great Plains and see the Rocky Mountains (1742–43). We know very little about their journey. All we know comes from a journal found in the French archives in 1851, another document in the French archives and a lead plate found buried near Pierre, South Dakota. The journal is difficult to interpret. The mountains they saw were probably the Big Horn Mountains of Wyoming, but they could have been the Black Hills or the Laramie Mountains. The journal states the trip may made by the "Chevalier Verendrye and one of his brothers" who are otherwise unidentified. Most likely the Chevalier was Louis-Joseph Gaultier de La Vérendrye and the brother was François de La Vérendrye but we cannot be sure.

The French founded Quebec City in 1608 and soon built a fur-trade empire throughout the Saint Lawrence River basin. From about 1690 they expanded southwest into the Mississippi River basin hoping to bottle up the English along the Atlantic coast. In 1720 the Spanish Villasur expedition left Santa Fe to contact the French, but was defeated by the Pawnee in Nebraska. In 1739 the first European crossing of the Great Plains was made by Pierre Antoine and Paul Mallet who travelled from the Mississippi River to Santa Fe.

From 1730 the elder Vérendrye and his four sons began pushing French trade and exploration west from Lake Superior out onto the Canadian prairies. In 1738 the elder Verendrye and two of his sons left Fort La Reine at the south end of Lake Manitoba reached the Mandan country in North Dakota on the upper Missouri River. He was looking for a rumored "River of the West" that was thought to flow into the Pacific. He was told that it would take all summer to reach the lower part of the river and that there one could find men like Frenchmen who wore armor and rode horses. {In his journal Verendrye did not try to guess whether these people were French, Spanish or something else. He was told that the lower river was very broad and flowed to the southwest.} He left two men to learn the language (December 1738). Next year (September 1739) they reported back that every summer the Horse People (Gens du Chevaux) visited the Mandans to trade. The Horse People said that they knew of bearded white men to the west who lived in stone houses and prayed to the "great master of life" while holding what looked like husks of corn [books]. In 1741 the younger Pierre and another son again visited the Mandans, but we have no details. In 1743 he sent two sons to discover the "Sea of the West".

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