John Filson was born in Chester County, Pennsylvania, around 1747. He was the son of Davison Filson, also of Chester County. He attended the West Nottingham Academy in Colora, Maryland, and studied with the Reverend Samuel Finley, afterwards president of the College of New Jersey (later Princeton). Heitman's Historical Register of Colonial Officers reports a John Filson served as an Ensign in Montgomery's Pennsylvania Battalion of the Flying Camp and was taken prisoner at Fort Washington on 16 November 1776, during the Battle of New York.