When: October 31
Costumes, candy, and jack-o-lanterns — the spookiest night of the year where treats (and tricks) await.
Halloween descends from Samhain, the Celtic festival marking the end of harvest and the beginning of the dark half of the year. The Celts believed that on the night of October 31, the boundary between the living and the dead thinned enough for spirits to cross. Food was left at doorsteps as offerings — to appease wandering ancestors, to leave something for whatever came through the boundary in the night. The direct line from that practice to a child in a skeleton costume asking for a Reese's Peanut Butter Cup is long but traceable. The Catholic Church absorbed Samhain into All Hallows' Eve — the night before All Saints' Day — and the medieval church tradition of "souling" involved poor people going door to door offering prayers for the dead in exchange for "soul cakes," small spiced buns. The exchange of food for service at the doorstep: the mechanism of trick-or-treating was already in place. Irish and Scottish immigrants brought the holiday to America in the mid-19th century, where...