John C. Fremont is an important historical figure best remembered for his three explorations of the west in the 1840s. Fremont married Jessie Benton, daughter of Sen. Thomas Hart Benton in 1841. The Senator championed the idea of Manifest Destiny, pushing for national surveys of the West and arranging for his son-in-law to lead them.

From 1842 to 1846 Fremont led three explorations of the west with Kit Carson as guide and Charles Preuss as the topographer. His early route became know as the Oregon Trail and his explorations are credited with encouraging the huge overland migration to the west. He was the first American to see Lake Tahoe, and finally determined that the Great Basin is endorheic, or closed basin with no outlet to the sea.

Fremont went on to become a millionaire, a California senator, a governor to Arizona Territory, the man who is credited with saving Kit Carson's life, and much more, yet died penniless and in virtual obscurity. Some scholars regard Fremont as a hero of significant accomplishment, while others view him as a failure who repeatedly defeated his own best ideals. He remains an enigmatic figure in the history of the United States. Read more of his fascinating story here.

This map has been accorded twofold importance in the development of the westward expansion: first, as a major contribution to geographical and cartographical knowledge, and secondly, as historic documentation of Fremont's third expedition. The map is a remarkable graphic depiction of this expedition and is considered one of the most important 19th century American maps. It covers all of the western territories from the 105th Meridian. Among the most interesting features are the appearance of the term Golden Gate at the entrance to the Bay of San Francisco, the markings of the El Dorado or Gold Region in the California Gold Fields, a hypothetical east-west mountain range near the 42nd parallel, and a notation identifying the location of Mormon settlements for the first time. Wheat illustrates the map and devotes eight pages to its description.

Having been court-marshaled and dismissed from the Army in 1847, Fremont was not asked to publish the details of this last expedition by the Corps of Topographical Engineers as would normally be required. Instead, the Geographical Memoir comprised his report. It was published nonetheless by Congress at the behest of the powerful Senator Thomas Hart Benton, Fremont's father-in-law. The memoir is also known as Misc. Doc. No. 148, 30th Congress, 1st Session. This is the large, and increasingly rare, map from that report.

References: Wheat (TMW) #559; Wheat (Gold) #40; Goss (NA) #77; Schwartz & Ehrenberg plt. 171.

Condition: B+

Issued folding with light toning along the folds and one short fold separation in the top left blank margin that just enters the border and has been closed on verso with archival tape.