Trivia

During his first year of college, Robertson and some friends signed up for military duty after the Japanese bombed Pearl Harbor in 1941. He began his military service in Fort Sill, Oklahoma, before being sent to the horse cavalry at Fort Riley, Kansas, and then to officers' school at Fort Knox, Kentucky where he was commissioned a Second Lieutenant in the Armed Forces. From there he was sent to the Engineer School at Fort Belvoir, Virginia. After stateside training he served as a tank commander in the 777th Tank Battalion in the North African campaign. He was standing in the hatch when his tank was hit by enemy fire. His tank crew were killed, but he was blown out of the hatch and survived with shrapnel wounds to his lower legs, the scars of which he still bears. Fully recovered, he went on to serve with the 322nd Combat Engineer Battalion during the European campaign. He was wounded a second time, this one in the right knee during a mortar attack. Again he made a complete recovery.

Wounded twice during WWII while serving in the Army in North Africa and Europe, he was awarded the Bronze and Silver stars and a Purple Heart for his courage.

Inducted into the Hall of Great Western Performers of the National Cowboy and Western Heritage Museum in 1983.

Retired after he finished his role as Zeke in the TV series Harts of the West (1993) in order to spend more time at his Yukon, Oklahoma ranch and raise horses. Ill health forced him in recent months to move to the San Diego California area just months before his death of emphysema and pneumonia and he died at Scripps Memorial Hospital in La Jolla.

Married five times, Robertson had only one child, a daughter Rochelle (from his first marriage).

The son of Melvin and Varval Robertson, he attended Classen High School in Oklahoma City. Was a horse rider by age ten and was training polo ponies in his teens. During his junior year he was declared "ineligible" to play sports because of two professional boxing matches he had previously fought in. At the age of 17 he was attending Oklahoma Military College, and boxing in professional prize fights to earn money. Harry Cohn approached him after a fight in Wichita, Kansas and asked him to come out to Hollywood to play the role of Joe Bonaparte in a boxing picture called "Golden Boy." Robertson refused, saying he was in the middle of training 17 polo ponies, and could not leave his family at his age. William Holden eventually was cast in the L'Esclave aux mains d'or (1939) role.

On the June 25, 1987 episode of The Tonight Show Starring Johnny Carson (1962), Robertson said he was back doing television after retiring due to financial problems.