“Nice example of Thomas O. Larkin's map of the Sacramento Valley, including the newly discovered gold regions, the first printed map of the gold regions. Thomas Oliver Larkin was an early California merchant, who served as U.S. Consul to the Province of California and U.S. Consul to the Republic of California, following the Bear Flag Revolt. His 2 letters to the president in June 1848 are two of the earliest communications of the discovery of gold in California sent to the East and his map of the Sacramento Valley was the first printed map to show the Gold Regions. The map shows Ranchos in the Central Valley and along the American river has "Gold Region" on both sides. The original was traced from a map prepared for Bidwell in 1844.” raremaps.com
Image: davidrumsey.com
“The title words including the Gold Region and the designation of the Mining District on the map make this map by Thomas Oliver Larkin, the first and last U.S. Consul to Mexican California, one of the key maps of California history. As Carl Wheat points out in his great cartobibliography, The Maps of the California Gold Region, it ranks as “one of the earliest (if not the earliest)” to denote the discovery area along the American River. In creating this map, Larkin simply took the best-known map of the Sacramento Valley, John Bidwell’s manuscript map of 1844, traced it, and made additions. As delineated by Larkin, the Mining District occupied two ranchos bordering both banks of the American River: Rio de los Americanos Rancho of the late William Leidesdorff and Rancho San Juan of Joel P Dedmund. Larkin sent his tracing back to Boston for publication, and publisher T. Wiley, Jr., for protection, placed the lithographed, hand-tinted map in a protective black cloth folder with the magical words Gold Region gilded on the front cover. On the inside cover, Wiley added a paper label with the words “A Correct Survey Of The Gold Region California.” With a copyright date of 1848, this stands as one of the earliest examples of a publisher taking advantage of the gold fever that was just beginning to sweep across the nation. Given the map’s lack of detail, it can hardly be called a “correct survey”.” californiamapsociety.org
https://www.raremaps.com/gallery/detail/30256/map-of-the-valley-of-the-sacramento-including-the-gold-regio-larkin