The area around Trion was first settled by pioneer William Penn. The town is named for the trio of businessmen who founded Trion Factory—Andrew P. Allgood, his father-in-law Spencer S. Marsh, and Colonel William K. Briers. The history of Trion Factory—later The Trion Company, Riegel Textile and Mount Vernon Mills—is inseparable from the history of the town. Almost without interruption the company has been in production since 1846. In addition to the Allgood family from 1845 to 1912, the mill has been owned by the Benjamin D. Riegel family from 1912 to1987 and the R.B. Pamplin family since 1987.