what was Prima Aprilis in ancient rome?

Practical Jokes in Rome

April Fool's Day, or "Prima Aprilis" as it is known in some cultures, is not an ancient Roman holiday. While ancient Rome did have a festival called Hilaria that was celebrated on March 25th, it was a day dedicated to the goddess Cybele and was not associated with practical jokes or hoaxes. 

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The origins of April Fool's Day are not entirely clear, but it is believed to have developed as a European tradition sometime in the Middle Ages. The exact origins and history of the holiday are debated, but it is now commonly celebrated in many countries on April 1st as a day for playing practical jokes and spreading hoaxes.