Held on All Saints' Day (1 November) and All Souls' Day (2 November) according to the Catholic calendar, this Aztec-influenced festival commemorates the memory of deceased family, friends, and ancestors.

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It originally fell around August, but the Christian conquistadors, hoping to assimilate the heathen holiday through their favoured tactic of cultural mestizaje (mixing), moved it to the day after All Saints' Day.

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Both All Hallows' Eve -- known today as Halloween -- and All Saints' Day, which follows on November 1, were designated as days to pray for dead souls that had not passed out of purgatory, in the belief that the prayers of the living will help.

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