Speedy’s first appearance was in 1953’s Cat-Tails for Two though he appeared largely in name (and super speed) only. It would be two years before Friz Freleng and layout artist Hawley Pratt redesigned the character into his modern incarnation for the 1955 Freleng short Speedy Gonzales. The cartoon features Sylvester the Cat guarding a cheese factory at the international border between United States and Mexico from starving Mexican mice. The mice call in the plucky, excessively energetic Speedy (voiced by Mel Blanc) to save them. Amid cries of “¡Ándale! ¡Ándale! ¡Arriba! ¡Arriba! ¡Epa! ¡Epa! ¡Epa! Yeehaw!” (Spanish for “Go on! Go on! Up! Up!”, although “Ándale arriba” may have been intended as meaning “hurry up”), Sylvester soon gets his comeuppance. The cartoon won the 1955 Academy Award for Best Short Subject (Cartoons). in New Looney Tunes he appears to have reverted back to his personality from his earlier shorts in the episode Tweet Team.
He also is involved with the Sylvester the Cat problem and says his classic phrase too.