John Charles Frémont or Fremont was an explorer of the Western United States, military officer, and politician. He was a U.S. Senator from California, and in 1856 was the first Republican nominee for President of the United States. A native of Georgia, he was an opponent of slavery and participated in the California genocide.
In the 1840s, Frémont led five expeditions into the Western United States. While on the third expedition, he and his men committed a number of massacres against Native Americans in California. 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 after a conflict over 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. 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.