With Wyeth, on a second expedition in 1834, went the Reverend Jason Lee and four Methodist missionaries. Two years later came Dr. Marcus Whitman and another company of missionaries with their wives; they brought a wagon through South Pass and over the mountains to the Snake River, and began an agricultural colony. Thus the old story of the sequence of fur-trader, missionary, and settler was repeated. The possession of Oregon by the British fur-trader was challenged by the American farmer.
Contemporaneously with the development of the fur-trade in the Rocky Mountains, a trade was opened between St. Louis and the old Spanish settlements at Santa Fe. Although even in the days of Washington adventurous frontiersmen like George Rogers Clark had set their eyes on Santa Fe and the silver-mines of the southwest, it was not until the Mexican revolution (1821), when Spain's control was weakened throughout her whole domain, that systematic trade was possible. In 1822, Becknell, of Missouri, took a wagon-train to Santa Fe, to trade for horses and mules and to trap en route. Year after year thereafter, caravans of Missouri traders found their way across the desert, by the Santa Fe trail, with cottons and other dry-goods furnished from St. Louis, and brought back horses, mules, furs, and silver. The trade averaged about one hundred and thirty thousand dollars a year, and was an important source of supply of specie for the west; and it stimulated the interest of St. Louis in the Mexican provinces. The mode of handling the wagon--trains that passed between Missouri and Santa Fe furnished the model for the caravans that later were to cross the plains in the rush to the gold-fields of California.[Footnote: Gregg, Commerce of the Prairies; Chittenden, Am. Fur Trade, II., chap. xxix.] By 1833 the important western routes were clearly made known.[Footnote: Semple, Am. Hist. and its Geographic Conditions, chap, x.] The Oregon trail, the Santa Fe trail, the Spanish trail, and the Gila route [Footnote: Personal Narrative of James O. Pattie; H. H. Bancroft, Hist. of California, III., 162.] had been followed by frontiersmen into the promised land of the Pacific coast and the southwest. In the course of ten years, not only had the principal secrets of the topography of the Rocky Mountains, the Great Basin, the passes across the Sierra Nevadas been revealed, but also the characteristics of the Spanish-American settlements of California and the Rio Grande region. Already pioneers sought Texas, and American colonization was preparing for another and greater conquest of the wilderness.