Modern trick-or-treating may look like costumes and candy, but its roots are far older. The custom reaches back to Samhain, when people believed the veil between the living and the dead grew thin. Food was left outside homes to calm wandering spirits and keep them from causing trouble.

Centuries later, during All Souls' Day, the tradition shifted from spirits to people. The poor and children visited the homes of wealthier villagers to offer prayers for the dead. In return, they received a small round soul cake as a token of thanks.

When these customs crossed the Atlantic with Irish and Scottish immigrants, they slowly transformed into the Halloween ritual we know today. The spirits faded, the prayers disappeared, and the sweets remained.