The real history of Halloween

Great post, h/t Mark Shea, by Father Augustine Thompson, OP:

However, Halloween falls on the last day of October because the Feast of All Saints or "All Hallows" falls on Nov. 1. The feast in honor of all the saints in heaven used to be celebrated on May 13, but Pope Gregory III (d. 741) moved it to Nov. 1, the dedication day of All Saints Chapel in St. Peter’s at Rome. Later, in the 840s, Pope Gregory IV commanded that All Saints be observed everywhere. And so the holy day spread to Ireland. The day before was the feast’s evening vigil, "All Hallows Even" or "Hallowe’en." In those days, Halloween didn’t have any special significance for Christians or for long-dead Celtic pagans.

In 998, St. Odilo, the abbot of the powerful monastery of Cluny in Southern France, added a celebration on Nov. 2. This was a day of prayer for the souls of all the faithful departed. This feast, called All Souls Day, spread from France to the rest of Europe.

So now the Church had feasts for all those in heaven and all those in purgatory? What about those in the other place? It seems Irish Catholic peasants wondered about the unfortunate souls in hell. After all, if the souls in hell are left out when we celebrate those in heaven and purgatory, they might be unhappy enough to cause trouble. So it became customary to bang pots and pans on All Hallows Even to let the damned know they were not forgotten. Thus, in Ireland, at least, all the dead came to be remembered — even if the clergy were not terribly sympathetic to Halloween and never allowed All Damned Day into the Church calendar.