John Charles Frémont or Fremont (January 21, 1813 – July 13, 1890) was an American explorer, military officer, and politician. He was a US Senator from California, and in 1856 was the first Republican candidate for President of the United States. During the 1840s, he led five expeditions into the American West, and became known as The Pathfinder.
During the Mexican–American War, Frémont, a major in the U.S. Army, took control of California from the California Republic in 1846. Frémont was convicted in court-martial for mutiny and insubordination over a conflict of who was the rightful military governor of California. After his sentence was commuted and he was reinstated by President Polk, Frémont resigned from the Army. Frémont led a private fourth expedition, which cost ten lives, seeking a rail route over the mountains around the 38th parallel in the winter of 1849. Afterwards, Frémont settled in California at Monterey while buying cheap land in the Sierra foothills. When gold was found on his Mariposa ranch, Frémont became a wealthy man during the California Gold Rush, but he was soon bogged down with lawsuits over land claims, between the dispossession of various land owners during the Mexican–American War and the explosion of Forty-Niners immigrating during the Rush. These cases were settled by the U.S. Supreme Court allowing Frémont to keep his property. Frémont’s fifth and final privately funded expedition, between 1853 and 1854, surveyed a route for a transcontinental railroad. Frémont became one of the first two U.S. senators elected from the new state of California in 1850. Frémont was the first presidential candidate of the new Republican Party, carrying most of the North. He lost the 1856 presidential election to Democrat James Buchanan when Know Nothings split the vote. Democrats warned that his election would lead to civil war.