During the eighteenth century, as Spain and France vied for control of the interior of the North American continent between Canada and Mexico, various expeditions looked for trade routes across the region. Determined to find a way to expand their nation's market to Santa Fe, French traders looked for viable east-west routes from New Orleans and from Missouri. In 1739 the brothers Pierre Antoine and Paul Mallet, both French Canadian traders, explored a potential route from the Missouri River area to New Mexico; their return trip eastward in 1740 followed, at least in part, the Canadian River to its confluence with the Arkansas and then down that stream to New Orleans. They may have been the first to completely cross present Oklahoma.
In 1741–42, accompanied by André Fabry de la Bruyère, they tried to repeat their journey and returned westward via the Arkansas and Canadian. The dry conditions forced Fabry to turn back, and although the Mallets continued westward, they too were forced to abandon their mission. In 1750 on a third trip, this time from Kadohadacho Post up the Red River and then up the Canadian, the brothers were arrested and Pierre sent to Cuba. Although Mallet described the country and exposed the reality that the Canadian and Red were different streams, the Spanish took scant notice of the information. The geographical mysteries of the Louisiana country remained unrevealed until a survey of the Red River boundary was ordered after the Adams-Onís Treaty of 1819.