Naashon is an alternate spelling of the name Nahshon found in Exodus. He was the son of Amminadab, of the tribe of Judah. His sister Elisheba became the wife of Aaron the high priest, making Naashon Aaron's brother-in-law.
1.John McClintock and James Strong, "Nahshon," in Cyclopedia of Biblical, Theological and Ecclesiastical Literature, vol. VI (Harper & Brothers, 1867–1887).