Christopher Dark was born Alfred Francis DeLeo in NYC in 1920. He started acting onscreen in 1950. He played a lot of character roles, especially lawmen and military men. He appeared on David Dotort's other show The High Chaparral, as well as The Lone Ranger, several episodes of The Wonderful World of Disney, and Shirley Temple's Storybook. Christopher was married and had one child. He was good friends with Guy Williams, who played the Cartwrights' cousin Will on Bonanza. Sadly, Christopher died of a heart attack in 1971, when he was 51.
Christopher Dark on Gunsmoke