Just before the California Gold Rush

In 1848, the United States was vitally interested in the western territories of the continent that eventually became California, Nevada, Utah, Colorado, Arizona and New Mexico.

The United States had just forced a defeated Mexico into the Tready of Guadalupe Hildago to end the Mexican-American War. An 1848 map of the region published for the United States Senate is in the collection of rare and unusual items at Lighthouse Books, ABAA. It shows the territory contained in the Mexican Cession.

The map was drawn by Charles Preuss, a mapmaker who traveled with explorer John C. Fremont on his expeditions through the American west. It was based on the surveys of Fremont, who made several trips to explore the lands between the Mississippi River and the Pacific Ocean.

The expeditions were a huge success and widely celebrated among Americans in the east. The penny press of the day dubbed Fremont The Great Pathfinder. The explorations were probably the most successful thing Fremont did in his life. (He later ran unsuccessfully for president and was fired as a general in the Civil War, but that’s another story.)

The map was published just before the California Gold Rush of 1849. Swiss pioneer John Sutter owned a sawmill at Nueva Helvetia, which means New Switzerland in Spanish. The location is shown on the map. On January 24, 1848, Sutter’s carpenter, James Marshall, discovered gold in the American River nearby. This map was published shortly after that discovery but before the Gold Rush got into full swing the following year. Neither Sutter nor Marshall ever profited from the discovery of gold.

The map also shows the border with Mexico along the Gila River that was established by the treaty on February 2, 1848 and the city of Santa Fe, which had long been established since the arrival of European explorers. It also locates the Great Basin and the Great Salt Lake in what eventually became Utah.

The map is labeled “Profile of the traveling route from the South Pass of the Rocky Mountains to the Bay of San Francisco.” It shows the Humboldt River running through northern Nevada, which Fremont explored and named. The Humboldt became the route of the California Trail that the ‘49ers used to get to the gold fields. The upper left corner of the map displays the locations of Mount Olympus, Mount Rainier and Mount St. Helens.

The map was printed by E. Weber and Company, an important Baltimore lithographer of the era, who had previously produced maps connected with Fremont’s explorations.