The Bidwell-Bartleson party of 1841 even after 156 years still has not has not received the full acknowledgement for their accomplishments. They proved that overland travel to California was feasible and possible even with wagons. With an experience and knowledgeable guide they would have established the wagon road to California that could have been used by the thousands of future emigrants. Dr. Doyce B. Nunis, Jr. in his book, "The Bidwell-Bartleson Party," 1841 California Emigrant Adventure, states in the introduction page 3.
John Bidwell has been hailed by his principal biographer as the 'Prince of California Pioneers.' That appellation is well deserved, for it was earned by six decades of important contributions to the development of his adopted state. From the very onset of his arrival in Mexican California, November 4, 1841, he began to make his mark on the future thirty-first state in the Union. While clerking for John A. Sutter at Bodega Bay, his first job in California, Bidwell commenced a lengthy letter to a Missouri friend, Elam Brown. As he later wrote to historian Hubert H. Bancroft in 1884, 'I promised items of our journey and of the country here &c.' He categorically stated, 'I never wrote it for publication. . . [but the letter] happened to get into the hands of a printer in Missouri.'
And thus Bidwell's diary was read and carried by westward travelers, becoming the first overland emigrant "guide".