Americans spend billions each year on this holiday, making it second to Christmas in its earning potential annually. Thus the main motivation for perpetuating it…plus it can be fun.
Around 2,000 years ago, the Celts, who lived in what is now the United Kingdom, Ireland, and northern France, had a festival commemorating the end of the year. Their New Year was November 1, and this festival was called Samhain, pronounced sow-en. The end of their year signaled the end of summer, the end of the harvest season, and the beginning of a long, hard winter that often caused many deaths of animals and people. Weaker livestock were often killed and eaten during this holiday, since most likely, they would not survive the winter anyway. Because of this perception- this time of year signified death to the Pagan Celtics. The people believed that the night before the New Year, the wall between the living and the dead was open, allowing spirits of the dead, both good and bad, to mingle among the living.
SOURCE …”…earning manufacturers billions of dollars”, yet again commercialism, capitalism steers American customs
Some of these spirits were thought to possess living people, cause trouble, ruin crops, or to search for passage to the afterlife.
Samhain was considered a magical holiday, and there are many stories about Celtic practices and beliefs during this festival.
Some say the spirits unleashed were those of the ones who had died in that year. Offerings of food and drink were left to aid the spirits, or to ward them away. Other versions say the Celts dressed up in outlandish costumes and roamed the neighborhoods making noise to scare the spirits away.
Faeries were believed to roam the land during Samhain, dressed as beggars asking for food door to door. Those that gave food to the faeries were rewarded, while those that did not were punished by the faeries. This is reported to be the first origin of the modern “trick or treat” practice.
Over the next several hundred years, Christianity had spread to include the lands inhabited by the Celtics and the Romans, but the festival of Samhain was still celebrated by the people.
As with most holidays rooted in paganism, The Christian church reportedly did not like the festivals and wanted to deter them from being practiced by Christians, so a replacement was needed.
Pope Boniface IV designated May 13 as All Saints Day to honour dead church saints and martyrs. Samhain continued to be celebrated, so in 835 A.D., Pope Gregory IV moved the holiday to November 1, probably to take attention away from the Pagan Samhain festival and replace it. Since All Saints Day was sanctioned by the church, and related to the dead, the church was happy, but many Pagan traditions of Samhain continued to be practiced, including bonfires, parades, and dressing up in costume.
All Saints Day was also known as All Hallows, or All Hallowmas (Hallowmas is Old English for All Saints Day). Since Samhain was celebrated the night before November 1, the celebration was known as All Hallows Eve, and later called Halloween. In the year 1000 A.D., the church designated November 2 as All Souls Day, to honour the dead who were not saints, and they eventually became combined and celebrated as Hallowmas. SOURCE