The ultimatum given by children who call on houses to solicit gifts at Hallowe'en.
There could hardly be a better example of the way that language and traditions migrate over time and across different cultures than trick or treating. This is well-known to be an American tradition, but its origins lie in medieval Europe.
There are myriad Christian and pagan rituals and celebrations that have taken place on or about the 1st of November each year. These occurred in virtually every English-speaking and/or Christian country. They have evolved and merged over the centuries and continue to do so. Common features of these traditions are - asking for food, dressing in disguise and a connection to the spirits of the deceased.
The language of these traditions is heavily influenced by the naming of days in the Christian calendar. The central date of the rituals that herald the beginning of winter is the 1st of November, called All Saints Day or All Hallows Day. The following day is All Souls Day and the 31st of October is All Hallows Eve - shortened to Hallowe'en (i.e. the evening before All Hallows Day).
The practice of souling - going from door to door on or about All Souls Day to solicit gifts of food in return for prayers for the dead - evolved from a pagan ritual that was practiced all over Europe, possibly as early as the 10th century. As a Christian tradition it goes back to at least the 14th century, when it is mentioned by Chaucer. It is still commonplace in many Catholic countries, notably Ireland, where soul-cakes are left out for the departed. The first reference to the practice under that name in England is John Brand's Popular Antiquities of Great Britain, 1779:
"On All Saints Day, the poor people go from parish to parish a Souling, as they call it."
The tradition has altered so that it is now children, usually dressed in disguise, who go about asking for gifts around the beginning of November. Some examples of this are from:
England, where we have requests for 'a penny for the guy'. This derives from the bonfire celebrations that began to celebrate the thwarting of the Gunpowder Plot in 1605. Guy Fawkes was the explosives specialist of the plot. He was scheduled to be hanged, drawn and quartered, but escaped that fate by prematurely hanging himself by jumping from the scaffold with the noose around his neck. He is now symbolically re-executed each year on 5th November (Bonfire Night), when effigies of him, called guys, are burned on bonfires all over England. The 'pennies' that children collect are traditionally spent on fireworks. This had a secular and political rather than religious or supernatural motivation, but it clearly inherited much from souling.
The USA, where the tradition is trick or treating. This 20th century tradition has many of the features of the earlier rituals, a knowledge of which were of course brought to the USA by immigrants from Europe.
Scotland, where it is called guising. This is a clear predecessor of trick or treat. The main difference between the two was that the children performed small entertainments before being given gifts - poems, jokes etc. This is now merging into trick or treating, with sweets being expected without the party piece.
The earliest known citation of trick or treat in print is from an item in the Oregon newspaper The Oregon Journal, 1st November 1934, headed 'Halloween Pranks Keep Police on Hop':
"Other young goblins and ghosts, employing modern shakedown methods, successfully worked the 'trick or treat' system in all parts of the city."
Trick or treating spread across the USA in the 1930s and is cited then in newspapers from many states. For example, the Indiana paper The Vidette-Messenger, October 30th 1937:
"Trick or treat. This seems to be the popular pastime among the younger folk and Valparaiso people... will hear it many times tonight, for it is Hallowe'en."
From Washington state we have The Centralia Daily Chronicle item for 1st November 1939:
"Pranksters were bought off when oldsters complied with their 'trick or treat' demand..."
It seems that the practice wasn't universally popular amongst adults when it appeared in the 1930s. Many of the early references to trick or treating feature 'what's the world coming too' type comments by outraged residents and police. The Reno Evening Gazette, 1st November 1938, alludes to Nevada children using methods similar to the protection rackets of the Mafia. Its piece was headed 'Youngsters Shake Down Residents':
"Trick or treat was the slogan employed by Halloween pranksters who successfully extracted candy fruit from Reno residents. In return the youngsters offered protection against window soaping and other forms of annoyance."
Trick or treating was well-enough established in Montana by the end of the 1930s for The Helena Independent newspaper to be advertising a 23 cent "Trick or Treat Mix" of candies. It isn't clear how many they sold though. On 2nd November 1938, the same paper reported that some of their readers had not taken kindly to being given 'an offer they can't refuse' by small mask-wearing ghosts and ghoulies and, although they were threatened with little more than some impromptu window soaping, they expressed their annoyance in no uncertain terms - by shooting at the little devils.
"Hallowe'en pranksters in several sections of the nation carried home loads of buckshot last night. Most persons are not in favor of shotgun treatment, but they are in favor of some chastisement."
A ring on the doorbell, followed by "trick or treat?", is heard in households in many countries around the world each 31st October. There are several reasons for the international spread. Partly it is due to the migration of US families and partly to the cultural dominance of the USA (what child with a television set can have failed to have seen Spielberg's ET or at least one of The Simpsons' seventeen Treehouse of Horror Halloween Specials?). Probably more significant though are the commercial interests of the media and manufacturers. If you can get away with spending just 23 cents this Hallowe'en or Bonfire Night you'll have done well.