His career started with bit roles in 1948 in “Johnny Belinda” and “The Boy With Green Hair” and grew into films such as “Two Flags West” with Joseph Cotton and “O. Henry's Full House” with Richard Widmark and Marilyn Monroe.
His small screen credits include the starring role in “The Iron Horse” (1966-68), host and occasional star of “Death Valley Days” (1968-72), a recurring guest-shot on “Dynasty” in the early 1980s, and star of the short-lived “J.J. Starbuck” in the late '80s.
El Camino Memorial Encinitas mortuary in Encinitas, Calif., is handling arrangements. Robertson's niece said memorial services are pending in Rancho Santa Fe, Calif. Donations may be made to the Central Oklahoma Salvation Army.
Robertson is survived by his wife, Susan; his daughters, Rochelle Robertson, of Los Angeles, and Rebel Lea Robertson, of Dallas; and one granddaughter, Jade Robertson.