27 NOV--This Day in US Military History

1826 – Jedediah Smith’s expedition reached San Diego, becoming the first Americans to cross the south-western part of the continent.

He crossed the Mohave Desert and the San Bernadino Mountains from Utah. In 1826 at the Cache Valley summer rendezvous, in what is now northern Utah, but at that time a part of Mexico, General William H. Ashley sold out his interests in the fur trade to Jedediah Smith, David Jackson, and William Sublette. Following the purchase, Smith and seventeen fellow trappers began the famous South West Expedition, which proved to be instrumental in combating the pretensions of Mexico, Great Britain, France, and even Russia, to a vast domain, which would become (in large part) the western United States.
Those eighteen men became the first non-indigenous people to traverse the harsh Mojave Desert, before reaching California in November 1826. They had also been the first to cross the high Sierra Nevada range of the Rockies and the Great Basin, the latter encompassing most of Nevada, along with parts of Utah, California, Oregon, and Idaho. In the process the expedition disproved the existence of a river, which it had been thought could be found, with an unobstructed flow from the Rocky Mountains to the Pacific Ocean near San Francisco.

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