Explorations
In 1726 his fortunes changed when his brother Jacques-René was appointed the commander of the poste du Nord. This was the north shore of Lake Superior with three main posts: Fort Kaministiquia, which was a terminus for the main route west; a post at the mouth of the Nipigon River; and one near the future site of Wawa, Ontario, which had river connections to James Bay. La Vérendrye began trading in the area and in 1728 was appointed as commandant when his brother left to fight the Meskwaki.
He became involved with the quest to find a route to the Pacific, what was known as the Northwest Passage. Under the 1713 Treaty of Utrecht, Great Britain had taken control of Hudson Bay and thereby blocked the French from using that area. At this time people thought that not far to the west was an inlet from the Pacific called the mer du couchant, similar to the equally mythical Strait of Annian. They thought also that travelers could cross the height of land and find a River of the West that flowed all the way to the Pacific. (For the area to be explored see Early Canadian canoe routes, Nelson River Basin.)
In 1688 Jacques de Noyon had reached Rainy Lake. In 1717 Zacharie Robutel de La Noue tried to reach Rainy Lake but succeeded only in establishing Fort Kaministiquia. The British on Hudson Bay heard reports of coureurs des bois west of Lake Superior, but they left no records in the French archives. Morton thinks they may have gotten as far as Lake Winnipeg. In 1716 a memoir drawn up by Governor Vaudreuil showed lakes and portages as far as Lake of the Woods, from which flowed a river to the "Sea of the West". This implies that Frenchmen had explored west of Lake Superior before Vérendrye did so.
La Vérendrye questioned the Natives who came to trade. He learned of the Mandan country on the upper Missouri River. These people were described as white men who lived in big houses. Auchagah, a Cree guide, made a map of the canoe routes between Lake Superior and Lake Winnipeg based on his and other Cree experience. La Vérendrye judged correctly that Lake Winnipeg was the geographic key which had to be reached to allow further exploration.
In 1730 he met Governor Beauharnois at Quebec and worked out a plan. La Vérendrye would build a post on Lake Winnipeg. The expedition would be paid for by Quebec merchants who hoped to profit from the resulting fur trade. This financing was fragile because the merchants lacked the capital and organization to efficiently move supplies so far to the west. An additional goal was to divert furs from being traded to the British on Hudson Bay. In the absence of government funds, exploration was dependent on financing from the fur trade. It is not clear whether La Vérendrye was genuinely interested in exploration or whether exploration was a pretext for expansion of the fur trade. Maurepas, the French Minister of Marine, was very interested in exploration, but would not provide funds. According to Pehr Kalm, La Vérendrye was acting upon orders given by de Beauharnois to explore until he could reach the ocean.
In 1731 La Vérendrye, three of his sons and 50 engagés left Montreal. That autumn his son Jean-Baptiste built Fort St. Pierre on Rainy Lake. Next year they built Fort St. Charles on Lake of the Woods, which became his headquarters for the next several years. In 1733 Jean-Baptiste got within 20 miles of Lake Winnipeg but was blocked by ice and lack of supplies. In 1734 their party reached Lake Winnipeg. Jean-Baptiste built Fort Maurepas near the mouth of the Red River at the southern end of the lake. In 1734 La Vérendrye went to Quebec to reorganize the finances and returned to the western post the following spring. In 1734 more than half the beaver pelts reaching Quebec came from La Vérendrye's posts. But by 1736 it was clear that the supply system was not working, and Jean-Baptiste was forced to go to Lake Superior for supplies. He along with 20 other Frenchmen, 19 voyageurs including the Jesuit missionary priest Jean-Pierre Aulneau who accompanied them, were killed by the Sioux on Massacre Island in Lake of the Woods. La Vérendrye restrained the local Cree from a war of revenge in order to protect the fur trade. In 1737 La Vérendrye returned to Quebec on business.
In Paris, Maurepas was pushing for more exploration. By this time explorers had identified two candidates as the 'River of the West'. The correct one was the Saskatchewan River, which flows east into Lake Winnipeg. The other was the Missouri River in the Mandan country in what is now North Dakota, United States. The Mandan were said to live in big houses and resemble Frenchmen. La Vérendrye picked the Missouri. In September 1738 he reached Fort Maurepas on Lake Winnipeg and ascended the Assiniboine River to Portage la Prairie, where he built Fort La Reine just south of Lake Manitoba (October 1738).
Joining a large band of Assiniboines, he pushed southwest across the prairie and reached a Mandan village probably somewhere near the modern New Town, North Dakota, about 70 miles east of the Montana border. He did not push on to the Missouri River but sent his son Louis-Joseph to do it for him. In order to get rid of their numerous Assiniboine guests, the Mandan claimed that there was a Sioux war party in the area. The Assiniboines fled, taking with them the Cree interpreter. Unable to talk to the Mandan, La Vérendrye left two Frenchmen to learn the language and returned to Fort La Reine (January 1739).
Later in 1739, La Vérendrye's son was killed in battle with the Ojibwe and Dakota. The French held the Dakota solely responsible, with La Vérendrye declaring in a fit of rage "Rub these people out, and wipe them off the face of the Earth!" This incident was the final breaking point that resulted in the Dakota-Ojibwe War.
In 1740 he returned to Quebec on business, and in 1741 started on his fourth and last journey west. From Fort La Reine he sent his son Louis-Joseph exploring westward as far as, probably, the Big Horn Mountains of Wyoming (1742–43). (See: Verendrye brothers' journey to the Rocky Mountains) He worked to consolidate his hold on the chain of lakes that look like a single lake west of Lake Winnipeg, establishing Fort Dauphin (Manitoba), Fort Bourbon and Fort Paskoya. Back in France, Maurepas was growing increasingly irritated with La Vérendrye, who he thought was trading in furs when he should be exploring. In 1742 Maurepas suggested that he be replaced.
In 1743 La Vérendrye resigned. He returned to New France and led the life of a gentleman while doing a considerable business since his sons remained as traders in the west. In 1746 he was reappointed to his old post. He was planning the fifth expedition, this time up the Saskatchewan River, when he died on December 5, 1749. Shortly before his death, he was awarded the Order of Saint Louis.
