Seymour is a census-designated place (CDP) and unincorporated community in Blount and Sevier counties in the U.S. state of Tennessee. The CDP population was 10,919 at the 2010 U.S. census. It is included in the Knoxville, Tennessee Metropolitan Statistical Area.HistorySeymour was originally the site of Newell's Station, a frontier station established by early Sevier County pioneer Samuel Newell in 1783. The first court of Sevier County, State of Franklin, was held at Newell's Station in March 1785. During the 19th century, the community was known as Trundles Crossroads, where the main road from Sevierville forked, with one branch continuing northward to Knoxville and one branch westward to Maryville .Upon completion on December 18, 1909, of the Knoxville, Sevierville and Eastern Railway, the community's station was named Seymour in honor of the line's chief engineer, Charles Seymour. The Trundles Crossroads Post Office changed its name soon after to reflect the community's new designation.