The great thrust for westward expansion of the United States during the early 1820’s started a trail of beaver trappers, fur traders, and explorers across the vast, high prairies and plains to the Rocky Mountains. Mountain men were rugged and restless individuals, molded from the lot that was never content to settle in one place for very long. They were drawn by the call of the unbroken trail and the challenge of carving out a dangerous life in the heretofore, uncharted, and forbidding West. For many, it was a good living. By 1840, the price for beaver fur had dropped dramatically, ruining most traders and forcing trappers to seek new ways to make a living. Those who stayed were among those who sought out new trade routes, lured by the wealth of the Santa Fe Trail, and the charms of Spanish California. The mountain men became the first to extensively explore the Western North American continent, being driven among other things, to know what lay over the next high ridge.