Smith’s explorations paved the way for a notable influx of American trappers to the valleys west of the Sierra Nevada. Smith, in fact, returned to California that same summer. Pattie, Young, Ogden, Wolfskill, Jackson, and Walker all brought parties to the new fields during the first five years following the Smith venture. Fur traders informed the settlers in the western states of the easy life in California and enticed them with stories of the undeveloped resources of the Pacific slope. Pioneers were then occupying much of the country just west of the Missouri, and a gradual tide of westward emigration brought attention first to Oregon and then to California. The presence of Americans in California greatly annoyed the Mexican officials of the country. The fears of these officials were justified, for the trappers scarcely concealed their desire to overthrow Mexican authority and assume control themselves. To add to the threatened confusion, revolt brewed among the Mexicans who held the land. In 1832 Captain B. L. E. Bonneville secured leave of absence from the United States Army and launched a private venture in exploring and trapping. One Joseph Reddeford Walker, who had achieved fame as a frontiersman, was engaged by Bonneville to take charge of a portion of his command. Walker’s party of explorers was ordered to cross the desert west of Great Salt Lake and visit California. Reliable knowledge of the Sierra Nevada and the first inkling of the existence of Yosemite Valley resulted from this expedition, made in 1833. Joseph Walker, born in 1798 on the Tennessee River near the present Knoxville, Tennessee, had moved westward with the advancing frontier in 1818 to the extreme western boundary of Missouri. There he and his brothers rented government land near the Indian Factory, Fort Osage. They put in a crop and during slack seasons mingled with the Osages and the Kanzas Indians. Here Walker formed his first ideas of trade with the Indians—ideas which bore fruit during his later experiences on the Santa Fe Trail and with the fur brigades in the Rocky Mountains. Early in 1831, Walker, enroute southward from his home to buy horses, stopped at Fort Gibson in the heart of the Cherokee Nation in the eastern part of the present Oklahoma. Several companies of the 7th U. S. Infantry were stationed here. This circumstance brought about a sequence of events which left permanent marks upon Walker’s personal career and upon the history of the American West. Captain B. L. E. Bonneville was in command of B Company of the 7th Infantry. Bonneville confided in Walker that the government was about to place him on detached service in order that he might conduct a private expedition into the Rocky Mountains for furs and geographical data. He asked Walker to join him as guide and counselor. To this proposal Walker acceded enthusiastically and proceeded forthwith to organize the equipment and personnel needed for the venture.