César Julio Romero Jr. was an American actor and activist. He was active in film, radio, and television for almost 60 years. His wide range of screen roles included Latin lovers, historical figures in costume dramas, characters in light domestic comedies, and the Joker on the live action Batman television series of the mid-1960s, which was included in TV Guide's 2013 list of The 60 Nastiest Villains of All Time. He was the first actor to play the character.

Latin lover is a stereotypical stock character, part of the Hollywood star system. It appeared for the first time in Hollywood in the 1920s and, for the most part, lost popularity during World War II. In time, the type evolved, developing various local variants and gradually incorporating attributes other than the originally defining physical characteristics.