Halloween (or Hallowe’en, a contraction of All Hallows Evening) also known as All Hallows’ Eve or All Saints’ Eve, is a celebration on the eve of the Western Christian feast of All Hallows’ Day. It begins the three-day observance that is dedicated to remembering the dead, including saints (hallows), martyrs, and all the faithful departed.
It is widely believed that many Halloween traditions originated from the ancient Celtic harvest festival Samhain, and that this Gaelic observance was Christianized by the early Church, thus having Christian and pagan roots.
Historians tell us that throughout Ireland there was an uneasy truce existing between customs and belief associated with Christianity and those associated with religions that were Irish before Christianity arrived. Samhaim (pronounced SAH-win or sow-in), which comes from the Old Irish for “summer’s end,” was the first and most important of the four quarter days in the medieval Gaelic calendar and was celebrated in Ireland, Scotland and the Isle of Man. It was held on or about October 31st through November 1st (All Souls’ Day), and a kindred festival was held at the same time of year by the Brittonic Celts in Wales, Cornwall and Brittany.
Samhain marked the end of the harvest season and beginning of winter or the darker half of the year. It was seen as a luminal time, when the boundary between this world and the otherworld thinned. This meant the spirits or fairies could more easily come into our world and were particularly active. Most scholars see these spirits as degraded versions of ancient gods, who power remained active in people’s minds even after they had been officially replaced by religious beliefs.
At Samhain, it was believed that the spirits needed to be propitiated to ensure that the people and their livestock survived the winter. Offerings of food and drink or portions of the crops were left outside for the spirits. The souls of the dead were also said to revisit their homes seeking hospitality. Places were set at the dinner table and by the fire to welcome them. The belief that the souls of the dead return home on one night of the year seems to have ancient origins and is found in many cultures throughout the world. After this, the eating, drinking and games would begin. Special bonfires were lit and there were rituals involving them as well. It is suggested that the fires were a kind of imitative or sympathetic magic—they mimicked the Sun, helping the “powers of growth” and holding back the decay and darkness of winter.
Halloween activities include trick-or-treating, carving pumpkins into jack-o’-lanterns, lighting bonfires, playing pranks and visiting haunted attractions. In many parts of the world, the Christian religious observances of All Hallows’ Eve, including attending church services and lighting candles on the graves of the dead, remain popular, although elsewhere it has become a more commercial and secular celebration. (from Wikipedia and cutecalendar.com)