In 1845, Frémont was sent out again, in part because of the tensions between the U.S. and Mexico which would lead to armed conflict the following year. Frémont arrived in California just when local ferment led to an American rebellion which soon became part of the wider Mexican War. Frémont was appointed the first Governor of California, but soon became embroiled in a conflict with the military commander of California, General Stephen W. Kearny. This led to Frémont being sent back east under arrest and to his eventual court-martial and dismissal from the army.
As Frémont himself wrote in his Geographical Memoir, “The map has been constructed expressly to exhibit the two countries of Oregon and the Alta California together. [These territories officially became part of the United States between 1846 and 1848.] It is believed to be the most correct that has appear of either of them...” The importance of this map is indicated by the fact that Carl Wheat gave more space to the description of this map than to any other in his seminal Mapping the Trans-Mississippi West.
As the news spread of this discovery, through President Polk’s announcement on December 5th and then all the subsequent newspaper articles and private publications, there was an immediate demand for information on the gold strike, especially for maps which prospective prospectors could take with them. Many publishers rushed maps to the market, many containing spotty or completely erroneous details, but the maps which had any accuracy were mostly based on the Frémonth/Preuss map, which was without questions the best map of California available at that time.
The convenience of having maps that folded into a small size had been obvious ever since maps became items that were sold to the general public. For those wanting to take a map with them when they traveled, these maps could be easily carried in a pocket or bag. In the nineteenth century, these maps were printed onto banknote paper, which is tough yet thin, so it could be folded without as much wear. The maps were folded into covers and were usually brightly colored to make them easier to read when on the road. For those heading to the California gold fields, the need for such a map would be clear.
It isn’t clear who published the map, but given the use of the original stone Frémont may very well have been involved in its production—perhaps hoping to cash in on his explorations after their rather unpleasant ending. An extensive search has turned up only two copies of this version of the map, and while all pocket maps from the 19th century have a high attrition rate, this would seem to indicate that this map did not sell as well as the publisher would have hoped. This scarcity, and its historical significance, make it perhaps as desirable a map of related to the California Gold Rush as any. A true nugget from the California Gold Rush.