In his younger years Fremont had married Jessie Hart Benton, daughter of a successful US Senator. In the 1840’s he became an American hero exploring and mapping portions of the western US.
His popularity led him to become the first presidential candidate of the fledgling Republican Party, although he lost. While he and the second Republican candidate for president, Lincoln, may have shared political views, they didn’t share timing.
Fremont didn’t prove to be successful as a military commander in Missouri. As commander in the Western Department, he ordered all slaves in Missouri emancipated. Lincoln, who eventually would sign the Emancipation Proclamation, was not ready to do so in 1861 for fear that he would alienate the border states of Missouri, Kentucky, Delaware and Maryland, potentially losing their soldiers and resources to the Confederacy. Fremont refused an order to rescind his orders, and Lincoln fired him, a risky political move in itself due to Freemont’s popularity and connections.
Fremont was given a Mountain command in the east, but quit that when he became subordinate to Gen. Pope, who he felt he outranked. That ended his Civil War career, but he would eventually become Governor of Arizona territory. He passed away in New York in 1890.