Halloween originated from the ancient Celtic festival of Samhain, where people would wear costumes, usually related to animals or spirits. When the Romans conquered the Celtic regions, they incorporated aspects of their own festivals involving Pomona. The Christian church designated November 1 as All Saints' Day and the night before as All Hallows Eve, later shortened to Halloween. Modern Halloween traditions like trick-or-treating are descended from medieval practices of the poor going door-to-door seeking food.