"Halloween or Hallowe'en (a contraction of "All Hallows' evening"),[5] also known as Allhalloween,[6] All Hallows' Eve,[7] or All Saints' Eve,[8] is a celebration observed in many countries on 31 October, the eve of the Western Christian feast of All Hallows' Day. It begins the observance of Allhallowtide,[9] the time in the liturgical year dedicated to remembering the dead, including saints (hallows), martyrs, and all the departed.[10][11]
One theory holds that many Halloween traditions were influenced by Celtic harvest festivals, particularly the Gaelic festival Samhain, which are believed to have pagan roots;[12][13][14][15] some go further and suggest that Samhain may have been Christianized as All Hallow's Day, along with its eve, by the early Church.[16] Other academics believe Halloween began solely as a Christian holiday, being the vigil of All Hallow's Day.[17][18][19][20] Celebrated in Ireland and Scotland, in the 19th century, Irish and Scottish migrants brought many Halloween customs to North America,[21][22] and then through American influence, Halloween spread to many other countries by the 21st century.[23][24]
Halloween activities include trick-or-treating (or the related guising and souling), attending Halloween costume parties, carving pumpkins into jack-o'-lanterns, lighting bonfires, apple bobbing, divination games, playing pranks, visiting haunted attractions, telling scary stories, as well as watching horror films.[25] For some people, the Christian religious observances of All Hallows' Eve, including attending church services and lighting candles on the graves of the dead, remain popular,[26][27][28] although for others it is a secular celebration.[29][30][31] Some Christians historically abstained from meat on All Hallows' Eve, a tradition reflected in the eating of certain vegetarian foods on this vigil day, including apples, potato pancakes, and soul cakes.[32][33][34][35]"
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