Day of the Ninja is celebrated on December 5th every year. It started as a humorous counterpoint to the International Talk Like a Pirate Day (September 19th) and is a playful homage to ninjas, the stealthy and skilled agents of Japanese history and pop culture.

The day encourages dressing like a ninja, performing “ninja moves,” and engaging in ninja-themed fun. It’s a lighthearted celebration often embraced by fans of martial arts, anime, and samurai-era history. If you’re planning to celebrate, consider watching ninja movies, sneaking around playfully, or creating some ninja-themed crafts.