Origin of name
The term Halloween, originally spelled Hallowe’en, is shortened from All Hallows' Even – e'en is a shortening of even, which is a shortening of evening. This is ultimately derived from the Old English Eallra Hālgena ǣfen.[16] It is now known as "Eve of" All Saints' Day, which is November 1st.
A time of pagan festivities,[17] Popes Gregory III (731–741) and Gregory IV (827–844) tried to supplant it with the Christian holiday (All Saints' Day) by moving it from May 13 to November 1.
In the 800s, 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 once celebrated on the same day.
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