But even among the countries which do, you have to distinguish between those who celebrate traditionally and those who do it commercially.
Halloween is a festival that has its roots in Celtic pagan rituals, so traditionally it was celebrated in places such as Ireland, Scotland, Britanny, Wales or other Celtic regions.
Then there was the Great Irish Famine of 1845–49, which killed or forced the emigration of half the local population. A lot of the emigrants went to the USA, where they arrived with their traditions, but in the great melting pot of the USA when they were taking in people, it became the Halloween we know today.
And it’s this sort of “Halloween light “ that has bounced from the USA to the rest of the world, and Hell no, it’s not universal. At all. It was very recently imported in Switzerland, more through the greeds of retail chains than under the influence of the American or Irish expat community, and feels as natural here as I would on a nudist beach in Holland in December.
Nowadays shops will sell themed candies and kids have parties where they masquerade. In a sense to us Halloween is a late fall reprise of Carnevale, a holiday that occurs right before the start of Lent, and during which we dress up and play pranks. It’s essentially a commercial thing that very few people feel much affection for.
Halloween as we know it has been an exclusively American custom that only started spreading to the rest of the world since the 1960s. It is also — contrary much pop disinformation and urban legend — of fairly recent origin.
For example, trick-or-treating only goes back about a hundred years, and was the invention of CHRISTIAN YOUTH PASTORS and YMCA (Young Men’s CHRISTIAN Association) youth leaders, who promoted it as a wholesome and less vandalistic alternative to Mischief Night. Once Trick-or-Treating became tame, mothers ruined it for older boys by telling them to take their younger siblings along, and it thereafter became a little-kids’ activity, and the dark clothes, hoods, and masks were replaced with more flamboyant, fantastic costumes.