Halloween

Halloween’s origins date back to the Celts.

An excerpt from the article 21 facts about Halloween
October 31st was a night of pre-new-year celebration, called the Samhain festival. The Celts, a group of Indo-European peoples that lived 2,000 years ago, believed the world of the living and the dead mingled for a night, and the spirits of the dead, both good and vicious, had returned to walk the earth again.