Ventura was a member of the U.S. Navy Underwater Demolition Team during the Vietnam War. After leaving the military, he embarked on a professional wrestling career from 1975 to 1986, taking the ring name Jesse 'The Body' Ventura. He had a long tenure in the World Wrestling Federation (WWF) as a performer and color commentator and was inducted into the WWE Hall of Fame class of 2004.
However, I know Ventura best for his acting career. He played the parts of Blain Cooper in Predator (1987) and Captain Freedom in The Running Man (1987). He also had supporting roles in films such as Ricochet (1991), Demolition Man (1993) and Batman & Robin (1997).
I obtained Jesse Ventura's autograph through the mail in August 2015.
Links:
IMDb
Wikipedia