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.

BBC: Mexico's Day of the Dead

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.

BBC: Get spooked: Five sensational Halloween destinations

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.

CNN: Happy Halloween

After all, it is only the mass commercialisation of Halloween that is both new and American: it is more than a millennium since the Catholic church, attempting to convert the pagan Celts in Britain and Ireland, created All Saints or All Hallows Day to coincide with the Celtic festival honouring the dead.

ECONOMIST: Mexico, haunted by new ghosts

The commune, whose thousand or so residents are almost all progeny of the male founders, follows the precepts of the breakaway Fundamentalist Church of Latter-Day Saints based in Utah.

ECONOMIST: Just part of being free?