Halloween

When it falls

31 October, the eve of All Hallows (All Saints' Day, 1 November) in the Western Christian calendar, and of All Souls' Day on the second.

The Phala almanac gives the exact day for your own city; the lunar and solar rules above are what it computes from.

The story

It stands on Samhain, the Celtic festival of the end of the harvest and the start of winter, when the boundary between the living and the dead was held to thin and fires were lit against the dark. The Church set All Saints on the day after and the eve took the name All Hallows' Even. Irish and Scottish emigrants carried the turnip lantern, the disguise and the door-to-door begging to America in the nineteenth century, where the turnip became the pumpkin and the begging became trick-or-treat.

Mexico's Day of the Dead on 1 and 2 November, with its marigolds and sugar skulls, is a cousin from the same days with a different root.

How the day is kept

• The jack-o'-lantern, a pumpkin carved with a face and lit with a candle, on the doorstep.
• Children in costume going door to door for sweets after dark; houses decorated with cobwebs, skeletons and ghosts from the start of the month.
• Costume parties and parades; New York's Village Halloween Parade draws tens of thousands of marchers, and Salem in Massachusetts fills for the whole month.
• In Ireland, where it began, bonfires, barmbrack with a ring baked in, and games with apples.

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