White first served as a judge and state senator, before being nominated by the state legislature to replace Andrew Jackson in the U.S. Senate in 1825. In 1836, White ran unsuccessfully for president, representing the Whig Party. Anti-slavery and anti-secession sentiment ran high in East Tennessee in the years leading up to the American Civil War. William "Parson" Brownlow, the radical publisher of the Knoxville Whig, was one of the region's leading anti-secessionists (although he strongly defended the practice of slavery). Blount County, just south of Knoxville, had developed into a center of abolitionist activity, due in part to its relatively large Quaker faction and the anti-slavery president of Maryville College, Isaac Anderson. The Greater Warner Tabernacle AME Zion Church, Knoxville was reportedly a station on the underground railroad. Business interests, however, guided largely by Knoxville's trade connections with cotton-growing centers to the south, contributed to the development of a strong pro-secession movement within the city. The city's pro-secessionists included among their ranks Dr. J.G.M. Ramsey, a prominent historian whose father had built the Ramsey House in 1797. Thus, while East Tennessee and greater Knox County voted decisively against secession in 1861, the city of Knoxville favored secession by a 2-1 margin. In late May 1861, just before the secession vote, delegates of the East Tennessee Convention met at Temperance Hall in Knoxville in hopes of keeping Tennessee in the Union. After Tennessee voted to secede in June, the convention met in Greeneville and attempted to create a separate Union-aligned state in East Tennessee. In July 1861, after Tennessee had joined the Confederacy, General Felix Zollicoffer arrived in Knoxville as commander of the District of East Tennessee. While initially lenient toward the city's Union sympathizers, Zollicoffer instituted martial law in November, after pro-Union guerrillas burned seven of the city's bridges. The command of the district passed briefly to George Crittenden and then to Kirby Smith, who launched an unsuccessful invasion of Kentucky in August 1862. In early 1863, General Simon Buckner took command of Confederate forces in Knoxville. Anticipating a Union invasion, Buckner fortified Fort Loudon (in West Knoxville, not to be confused with the colonial fort to the southwest) and began constructing earthworks throughout the city. However, the approach of stronger Union forces under Ambrose Burnside in the summer of 1863 forced Buckner to evacuate Knoxville before the earthworks were completed.