Yes, The Banshees Of Inisherin is a British movie
In the same way that Father Ted is actually a British TV show.
You'd be forgiven for thinking that there is no movie in existence more Irish than The Banshees Of Inisherin. Headed by a quartet of internationally recognisable Irish stars, set in a fictional but obviously Irish location, against the backdrop of a landmark point in Irish history. Written and directed by a man with Irish parents, and holds dual citizenship for Britain and Ireland.
So how was it on Sunday night's BAFTAs that The Internet™ lost its collective minds when The Banshees Of Inisherin went home with the Best British Movie award? Well, to quote a famous real-life conspiracy movie: "Follow the money..."
While the majority of the creative folk involved are mostly inarguably Irish, the actually folk who put up the money for the movie to be made come from mostly British production companies. The Banshees Of Inisherin was produced by Film4 Productions (based in London), Blueprint Pictures (based in London) and TSG Entertainment (based in New York).
In much the same way that Father Ted was actually a British show - despite, y'know, everything about it - because it was made by Hat Trick Productions and Channel 4 (both London based), the ownership of a property goes beyond its setting. To be facetious for a moment, The Martian is an American movie, and not, y'know, a martian movie just because of its setting.
There are some movies that feel so undeniably Irish that we do absolutely stake some creative claim to them - another being In Bruges, despite the fact that it is set in Belgium, but also wouldn't be considered a Belgian movie. But it does all come down to the money.
To that end, there are actually some movies made with Irish production funding that we probably don't consider to be Irish but that absolutely are. 2015's Room and 2018's The Favourite, both Oscar-winners, both not set in Ireland, but both produced by Element Pictures (based in Dublin), while upcoming horror Evil Dead Rise is co-produced by Wild Atlantic Pictures (also based out of Dublin).
So, yes, as much as it might hit your ear wrong to hear it, The Banshees Of Inisherin is a British movie. That still doesn't excuse literally any time the British claim an Irish performer as one of their own, mind.
The Banshees of Inisherin is available to watch at home right now on Disney+, and will also be shown on the big screen as part of Omniplex's Oscar screening season.