On November 4, after nearly seven months on the trail, the Bidwell-Bartleson caravan crossed the Stanislaus River and reached Mount Diablo, fifty miles from San Francisco, becoming the first train of Western emigrants to enter the new California Territory.

The party, led by John Bartleson and Paul Geddes, had left Sapling Grove, Missouri (now Kansas), in the spring and joined forces with the missionary Father Pierre Jean De Smet and several Jesuit priests. Bartleson’s group hoped to establish homesteads and live in the perpetual spring that explorers had promised awaited them in the Pacific territory. The twenty-two-year-old John Bidwell, who had heard similar stories as a member of a Western Emigration Society in his Missouri town of Weston, helped organize the caravan and eventually became its secretary.

Father De Smet’s goal was to build a mission among the Flathead Indians in Montana, and his group was headed there. De Smet’s group depended entirely on a mountain man, Thomas Fitzpatrick, who had been a trapper in the Rockies and was the only member of the party familiar with the country.

In July the expedition divided. De Smet and about half the original party, accompanied by Fitzpatrick, headed north along the Oregon Trail. The rest pushed on westward, among them Nancy Kelsey, the only remaining woman on the expedition, who was carrying her baby with her. Wagons had to be abandoned during the rest of the journey over deserts and mountains. The thirty-two travelers were butchering pack mules by the time they emerged from the Sierra Mountains in late October and were saved from starvation when they discovered a herd of deer. After feasting, they made the final leg of their journey to Mount Diablo.