Image: Everett Collection

Hugh O'Brian, best known as the titular character on the classic Western series The Life and Legend of Wyatt Earp, died Monday at the age of 91. 

O'Brian got his start in Hollywood as a contract player for Universal Studios, where he appeared in several films in the late 1940s and early 1950s.

In 1955, O'Brian crossed over to television, where he got his big break on the groundbreaking Western drama The Life and Legend of Wyatt Earp. The series, produced by Desilu Productions, premiered four days before Gunsmoke. 

O'Brian played the lead role in the series, loosely based on the life of frontier marshal Wyatt Earp in Wichita, Kansas.

After the program ended in 1961, O'Brian continued to make guest appearances on television shows like Perry Mason, Charlie's Angels and The Love Boat. He reprised his most famous role in 1990 on the series Guns of Paradise, and again in 1991 on The Gambler Returns: The Luck of the Draw. 

At the same time O'Brian appeared on television, he continued to appear in films. He had the distinction of being the last person John Wayne ever shoots dead in a movie, in the 1976 film The Shootist. 

In addition to acting, O'Brian spent much of his money and time on philanthropic causes. In 1958, the actor started Hugh O'Brian Youth, a leadership organization focused on teaching high school students how to become future leaders. As of this year, the program has over 470,000 alumni. 

According to the foundation, O'Brian passed away peacefully Monday morning in Beverly Hills, California. He's survived by his wife of 10 years, Virginia Barber.