The practice of dressing up in costumes and begging from door to door for treats on holidays dates back to the Middle Ages. The modern trick-or-treating resembles the late medieval practice of souling, when poor people would go from door to door on November 1 - the day of the Hallowmas - begging for food in return for prayers for the dead on All Souls Day - November 2.
The tradition originated in Ireland and Britain although similar practices were found as far south as Italy. Shakespeare mentions the practice in his comedy The Two Gentlemen of Verona, when Speed accuses his master of "puling - whimpering or whining - like a beggar at Hallowmas."
The custom of wearing costumes and masks at Halloween goes back to the Celtic tradition of attempting to placate evil spirits. In Scotland, for instance, the dead were impersonated by young men dressed in white garments with their faces masked, veiled or blackened.
The trick-or-treat tradition was practiced in the western United States in the 1930s and probably even earlier than that. It gained country-wide acceptance as it spread from the western United States to the east in the early 1940s, but was interrupted when sugar rationing was introduced in 1942. The "intermission" lasted until 1946. The sugar rationing ended in August 1947 and the trick-or-treat custom was resumed later that year.
The custom was propagated by the press and the radio. It become firmly established in popular culture when Walt Disney portrayed it in the cartoon Trick or Treat in 1952.
At the same time UNICEF got involved and conducted a national campaign for children to raise funds for charity while trick-or-treating.
The kids wear costumes and proceed from house to house asking for sweet treats with the question, "Trick or treat?" The "trick" part is a threat to play a trick on the homeowner or his property if no treat is given.
Trick-or-treating is one of the main customs of the Halloween celebration. Those who live in neighborhoods with children should have some candy ready if they do not want to become victims of a trick or two...
Wishing everyone a very spooky Halloween - Dominique