The Origins of Halloween
All over the world there are many different holidays the occur during the end of October. The most common is the holiday that is now known as Halloween.
The origins of the holiday that has come to be known as Halloween start with the ancient Celtic culture that existed over 2,000 years ago in the region that is now Ireland, the United Kingdom, and
northern France. Celts celebrated the new year on November 1st. This day marked the end of the harvest and the beginning of a cold dark winter, a time that is often associated with death.
The Celts believed that the night before the new year (October 31st) the boundary between the worlds of the living and the dead became very thin and the dead were able to return and walk the earth
once more. Although they believed that these spirits were capable of causing harm to the living they were welcomed because they supposedly allowed the Celtic priests (the Druids) to predict the future
more accurately. Because of this, the night was a festival for the people called Samhain, pronounced "sow-in" (like cow-in), which literally means "Summer's End".
In order to commemorate the holiday everyone would douse their hearth fires as the Druids built sacred bonfires where sacrifices of crops and animals were made to the gods. During the night of the
festival the Celts wore costumes made from animal skins in order to better tell each other's fortunes. At the end of the night all the people would relight their hearths with fire from the sacred
bonfires which they thought would give them protection from the coming winter.
As history went by, the Celtic culture was being conquered by the Roman Empire, and by 43 C.E. little remained. Like any invading culture, the Romans tried to do away with the existing culture of
the Celts and incorporate their own. They had two holidays in October, the day of Feralia and festival for Pomona. Feralia was a day of remembrance for the dead. Pomona is the Roman goddess of fruit
Eventually the Roman empire became weak, and Christian influence spread to the Celtic lands around 800 C.E. In the seventh century, Pope Boniface IV created the holiday "All Saint's Day" which took
place on the first Sunday after Pentecost. In the ninth century it was moved to November 1st by Pope Gregory III possibly in order to try to draw attention away from the other holidays.
The day before All Saint's Day (October 31st) was referred to as "All-hallows Eve" by the Christians. Eventually, this became "Hallowe'en", and now it's simply "Halloween".
Wikipedia's Halloween Entry
The History Channel's Halloween Exhibit
Celtic Spirit's Samhain Page