All Hallows' Eve

The term Halloween is shortened from All Hallows' Even (both "even" and "eve" are abbreviations of "evening," but "Halloween" gets its "n" from "even") as it is the eve of "All Hallows' Day," which is now also known as All Saints' Day. It was a day of religious festivities in various northern European Pagan traditions, until Popes Gregory III and Gregory IV moved the old Christian feast of All Saints' Day from May 13 (which had itself been the date of a pagan holiday, the Feast of the Lemures) to November 1. In the ninth century, the Church measured the day as starting at sunset, in accordance with the Florentine calendar. Although All Saints' Day is now considered to occur one day after Halloween, the two holidays were, at that time, celebrated on the same day. Liturgically, the Church traditionally celebrated that day as the Vigil of All Saints, and, until 1970, a day of fasting as well. Like other vigils, it was celebrated on the previous day if it fell on a Sunday, although secular celebrations of the holiday remained on the 31st. The Vigil was suppressed in 1955, but was later restored in the post-Vatican II calendar.

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