Jackson DeForest Kelley (January 20, 1920 – June 11, 1999) was an American actor known for his iconic roles in Westerns and as Dr. Leonard "Bones" McCoy of the USS Enterprise in the television and film series Star Trek.
Today would mark Kelley's 91st Birthday.
In 1956, years before being cast as Dr. McCoy, Kelley played a small supporting role as a medic in The Man in the Gray Flannel Suit in which he utters the diagnosis "This man's dead, Captain" and "That man is dead" to Gregory Peck. Kelley appeared as Lieutenant Commander James Dempsey in two episodes of the syndicated military drama, The Silent Service, based on actual stories of the submarine section of the United States Navy. In 1962, he appeared in the Bonanza episode entitled "The Decision", as a doctor sentenced to hang for the murder of a journalist. The judge in this episode was portrayed by John Hoyt, who later portrayed Dr. Phillip John Boyce, one of Leonard McCoy's predecessors, on the Star Trek pilot "The Cage". In 1963, he appeared in The Virginian episode " Man of Violence" as a "drinking" cavalry doctor with Leonard Nimoy as his patient (Nimoy's character did not survive). Just before Star Trek began filming, Kelley appeared as a doctor again, in the Laredo episode "The Sound of Terror." It is not clear whether these portrayals factored into his casting in Star Trek. Kelley played Dr. Leonard "Bones" McCoy from 1966 to 1969 in Roddenberry's Star Trek, went on to reprise McCoy's character in a voice-over role in Star Trek: The Animated Series (1973–1974), and the first six Star Trek motion pictures (1979 to 1991).
Excerpt from http://en.wikipedia.org/wiki/DeForest_Kelley