Halloween is NOT a Christian holiday.
Halloween is totally pagan.
Druids and moon worshippers...devil worshippers etc...
It began during the days of the persecution of the Church by the Emperor Diocletian.
It was originally called the "Commemoratio Confessorum" - Commemoration of the Confessors.
It was started because so many Christians died for the faith in the persecutions that the Christian community was unable to keep a record of all their names - All Saints' Eve and All Saints' Day are the Christian equivalent of the Tomb of the Unknown Soldier.
The holiday was later hijacked by occultists in the North Sea basin centuries after it was first established in Rome, Antioch and Damascus, mostly because October 31st, which was an otherwise meaningless date in the Mediterranean was the same day as a pagan observance in England and Denmark. Of course, the Christians who instituted All Saints' Day were not English and knew nothing of these practices.