 It was invented by an Italian chef in Mexico on July 4th, a century ago. Cesar Cardini, who lived in San Diego, opened his restaurant, Cesar's in Tijuana, the year before to avoid prohibition in the U.S. While running low on supplies over the busy holiday, he threw together what he had left, put it over lettuce, made it table side, inventing the Cesar salad we enjoy across the globe today.