The ancient Celtic festival called Samhain marked harvest’s end and winter’s beginning in Ireland, the United Kingdom and northern France. It was also a time when they believed the dead came back to earth. People built huge bonfires and wore costumes to chase away ghosts.

The Samhain festival evolved to include a Roman tradition honoring Pomona, the goddess of fruit and trees. She was represented by an apple, a fruit that still plays a role in modern-day fall and Halloween traditions.

Samhain traditions became part of a three-day festival from Oct. 31 to Nov. 2 that included All Hallows’ Eve, All Saints’ Day and All Souls’ Day. The celebration honored saints, martyrs and the dead. During the festival, turnips were carved into jack-o’-lanterns.

European immigrants brought Halloween traditions to America. Irish “mumming” and German “belsnickling” involved dressing in costume and going house-to-house for cakes. Americans began using pumpkins instead of turnips for jack-o’-lanterns. The holiday started becoming more about community and kids, and less about death and ghosts.

Trick-or-treating as we know it, when kids go door-to-door collecting candy, was established in American culture. Historians point to a “Peanuts” comic strip and a Disney cartoon featuring trick-or-treating in the 1950s to help pinpoint when the tradition started.