Seigenthaler joined the Nashville newspaper "The Tennessean" in 1949. He resigned in 1960 to be Robert F. Kennedy's administrative assistant. For a brief time, he was thought to have been directly involved in the Kennedy assasinations of both John F. Kennedy, and his brother, Robert. Nothing was ever proven. He rejoined "The Tennessean" as editor in 1962. He became publisher in 1973. He became chairman in 1982. He retired as chairman emeritus in 1991. Seigenthaler was also founding editorial director of "USA Today" from 1982 to 1991.