One young fellah nearly fell off his bicycle looking at our Halloween decorations

We’ve gone full-bore with the exterior decorations this year. Two not-very-weather-resistant giant spiderwebs loom out from the front of the house.

Yet this wasn’t sufficient: the postie delivered a giant inflatable light-up spider (yes, there’s a theme), that’s been arranged to look like it’s climbing up the wall. But, you know, symmetry: another one arrived a few days later and now this mini-swarm takes up most of the front garden.

I’m not responsible for this. It is the fruit of Herself’s artistic vision – tacky for this time of the year, classy for Christmas – all intended, of course, to provide gaiety to the area. With, perhaps, the side effect of us winning Halloween.

It’s working too: the gaiety part anyway. Where I’m typing these words is at the front of the house, so I’ve a clear view of people walking past. Pretty much everyone, particularly children, stop to have a gawp. One young fellah nearly fell off his bicycle. We may have to post a legal disclaimer by the front gate.

It feels a little odd to have taken such a bold Halloween stance. It’s all a bit look-at-me: which isn’t very Irish. But what I tell myself is that Halloween is an American import. And Americans love being looked at.

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I know what you’re going to say: No! we invented Halloween. It’s really Samhain and we were doing it thousands of years before anyone. And while it is true that we (and the Scots) brought the original tradition across the Atlantic, almost immediately it began to change due to the widespread availability of pumpkins, Christian influences, puritan disapproval, and a concerted push against pranking.

But most of all it changed for the reason most things change: because it became an opportunity to sell sweets, outfits and giant inflatable spiders.

There are some trace amounts of Celtic culture still in there, but it would be a serious stretch to claim that Halloween is Irish. Like many things that are “American”, it evolved from a stew of multicultural influences.

But if you stare long enough at any cultural artefact, or person, their nationality becomes more complex. Most Irish people contain bits of French or Viking or English. Go back even further, and our ancestors arrived here from Spain or, according to some recent research, Wales. Riverdance is Irish, but incorporates flamenco, Russian and tap dancing. Guinness is Irish, but Arthur didn’t invent porter. The English did.

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Culture of any sort isn’t fixed or exclusively owned by any one group. It tends to morph and move around: it seems to need to keep moving to avoid extinction.

And already there are differences in how the US version of Halloween is observed in different countries. American kids still say “trick or treat”, but in Canada they simply say “Halloween!” or “Bonbons, s’il vous plaît.” In Scotland, children are still expected to do something – sing a song or recite a poem – while in Ireland, what was once a festival celebrated around bonfires in fields and forests has now become exclusively urban. Kids living on farms or in rural areas are bussed into towns or don’t get to do it at all.

And no one says trick or treat. There’s no tricking either. It’s all about the sweets. First, the little ones come along, dressed like dinosaurs or cartoon characters. They rarely say anything: just stare at you open-mouthed. Then there are the slightly older groups, mostly girls, who have put a lot of thought into their outfits. There’s usually a theme, that they are keen to explain. Finally, a few uncostumed teenagers chancing their arm. They are completely mute.

In the Irish iteration, the costume choices are clever, but almost never spooky. This year, Daughter Number Four and her friends are going out as soft drinks. She’s chosen Diet Coke: the only spooky thing about this beverage is that Coke was originally concocted by a racist drug addict who marketed it as French.