The tomato fight has been a strong tradition in Bunol since 1944 or 1945. No one is completely certain how this event originated. Possible theories on how the Tomatina began include a local food fight among friends, a juvenile class war, a volley of tomatoes from bystanders at a carnival parade, a practical joke on a bad musician, and the anarchic aftermath of an accidental lorry spillage.
One popular theory is that disgruntled townspeople attacked city councilmen with tomatoes during a town celebration. Whatever happened to begin the tradition, it was enjoyed so much that it was repeated the next year, and the year after that, and so on. The holiday was banned during the Spanish State period under Francisco Franco for having no religious significance, but returned in the 1970s after his demise.
The festival is in honor of the town's patron saints, Luis Bertran and the Mare de Deu dels Desemparats (Mother of God of the Defenseless), a title of the Virgin Mary.