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John C. Frémont

January 21, 1813 - July 13, 1890

Topic- California A Continent Divided: The U.S.-Mexico War

John C. Frémont

January 21, 1813 – July 13, 1890

John C. Frémont—U.S. politician, explorer, mapmaker, and military commander—led numerous exploratory missions into the northwest and southwest, which facilitated Anglo settlement and U.S. expansion into those regions. During the U.S.-Mexico War, after leading Anglo insurgents against Mexican control of the province, he proclaimed himself Military Governor of Upper California. He is also known for being the first Republican Party candidate for the U.S. presidency in 1856.

Born in Savannah, Georgia on January 21, 1813, Frémont grew up in South Carolina, excelling at mathematics as a youth. He entered the U.S. Army's Corps of Topographical Engineers as a surveyor and engineer at the age of twenty-four, accepting commissions to survey and map the upper Mississippi, Missouri, and Des Moines Rivers. His expeditions encouraged Anglo migration into the west, much to the pleasure of his new father-in-law: expansionist Missouri Senator Thomas Hart Benton. Frémont, himself an enthusiastic supporter of U.S. western expansion, married Benton's daughter in 1841.

Two years later, he led an expedition that exceeded its commission. After exploring the Great Basin, Frémont and his party advanced through the Sierra Nevada during the winter. The expedition struggled to survive, but managed to return to the U.S. in the fall of 1844. Frémont returned to Washington D.C. to much fanfare. His subsequent writings about the west generated more support for Manifest Destiny.

In 1845, Frémont led a surveying expedition of about sixty men to locate the source of the Arkansas River. Upon completing the mission, his party advanced to Upper California. Historians do not entirely agree as to whether or not Frémont took the initiative on his own accord (he may have been ordered by the U.S. command), but he threw his lot in with Anglo settlers against Mexican rule of the province. Frémont and his men arrived in Upper California in early 1846, and set about assuring Anglo settlers that in the event of war with Mexico his forces would defend their settlements.

Mexican authorities ordered Frémont's party to leave California in March 1846. The party retreated to Oregon Territory, where Modoc Indians harassed it. Frémont and his men retaliated by unwittingly massacring a different Indian village.

In May 1846, the U.S.-Mexico War began. Frémont received a dispatch from the U.S. War Department that month—the contents of which remain unknown—then proceeded to support Anglo insurgents in Upper California who revolted that June. The Anglo settlers defeated the Mexican authorities in Sonoma, California, and proclaimed an independent California Republic in the "Bear Flag Revolution." Frémont's forces helped the settlers repel a Mexican counterattack on June 24. A growing army of Anglo settlers subsequently advanced into San Francisco a week later. U.S. forces arrived in California some weeks later and proceeded to conquer California.

Frémont, only a lieutenant colonel by 1847, ended up clashing with his superior officers that year when he took it upon himself to draft and sign the Treaty of Cahuenga with Mexican forces in Upper California, thus ending U.S.-Mexico hostilities in the province that January. Claiming that Commodore Robert F. Stockton appointed him U.S. Military Governor of California, Frémont assumed temporary control of the territory. Brigadier General Stephen Watts Kearney protested the supposed appointment, asserting that Stockton had no authority to place Frémont in command.

The War Department court-marshaled Frémont in November 1847. Although Frémont found himself convicted, Senator Benton prompted President James K. Polk to commute his sentence. Frémont subsequently resigned.

Following the U.S.-Mexico War, Frémont ran for and won a U.S. Senate seat in the new state of California in 1850. Land he acquired in the state proved rich in gold. He became very wealthy as a result.

Still tremendously popular in the nation for his exploratory efforts, Frémont ran as the Republican Party's first presidential candidate in 1856. He lost to Democratic candidate James Buchanan, largely because of his anti-slavery beliefs.

Frémont fought in the U.S. Civil War as a major general, but after a series of political and military blunders, President Abraham Lincoln rescinded his command.

During the Panic of 1873, Frémont lost much of his wealth. President Rutherford Hayes subsequently appointed him Governor of Arizona Territory. He served from 1878 to 1883. He died seven years later in New York City at the age of seventy-seven.


Crawford, Mark, David S. Heidler, and Jeanne T. Heidler. Encyclopedia of the Mexican-American War.. Santa Barbara: ABC-CLIO, 1999.

Encyclopedia Britannica. "John C. Fremont." Last modified on July 25, 2014.

Hawgood, John A. "John C. Frémont and the Bear Flag Revolution: A Reappraisal." Southern California Quarterly. Vol. 44. June 1962.

Spencer, Tucker C. The Encyclopedia of the Mexican-American War: A Political, Social, and Military History. Barbara: ABC-CLIO, 2012.

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