The original Trigger, named Golden Cloud, was born in San Diego, California. Though often mistaken for a Tennessee Walking Horse, his sire was a Thoroughbred and his dam a grade (unregistered) mare that, like Trigger, was a palomino. Golden Cloud made an early appearance as the mount of Maid Marian, played by Olivia de Havilland in The Adventures of Robin Hood (1938).
A short while later, when Roy Rogers was preparing to make his first movie in a starring role, he was offered a choice of five rented "movie" horses to ride and chose Golden Cloud. Rogers bought him eventually in 1943 and renamed him Trigger for his quickness of both foot and mind. Trigger learned 150 trick cues and could walk 50 ft (15 m) on his hind legs (according to sources close to Rogers). They were said to have run out of places to cue Trigger. Trigger became such a ham that as soon as he heard applause, he would start bowing and ruin that trick. Roger's most carefully guarded trade secret was to get Trigger housebroken.
Roy Rogers made many personal appearances with Trigger in tow. More than once, he escorted him up three or four flights of stairs at hospitals to visit with sick children. His horse was so important to Rogers that when he purchased a "Best Wishes for the New Year" advertisement in Variety, he signed it "Roy Rogers and Trigger". Trigger was ridden by Rogers in many of his motion pictures, becoming much loved by the youthful audience that saw him on film and in Rogers' 1950s.