Ricardo Montalban also had a Bonanza appearance before he became a legendary name on Star Trek and Fantasy Island. In a 1960 Bonanza episode, the Mexican-born actor played "Matsuo," an Indian who crosses paths with "Ben" (Lorne Greene).
Bonanza was famous for its cast of "Cartwrights," but the TV Western also featured notable guest stars across its 14 seasons. The range of guests included iconic movie stars and many up-and-coming actors who would later become A-list names.
In this gallery, we'll look back at the guest stars you probably forgot appeared on the show — starting with Leonard Nimoy! "Spock" himself acted in a 1960 episode, before again joining Bonanza for TV movie Under Attack in 1995. His future Star Trek co-star DeForest Kelley also had several Bonanza appearances.