I have a UK keyboard. It works. But in the top right corner of my Gnome Shell screen I have a little "en1⌄" menu which offers me a choice of UK or US keyboards.
As I have no plans to move across the ocean, being constantly offered a foreign keyboard layout is not useful; it is screen junk.
So I went to Keyboard Layouts and removed the US layout, leaving just the UK one. The menu disappeared - great...but turns out that now it thought my keyboard had gone all American - press # and I'd get \!
Enable the US keyboard, and it goes UK again(!).
It's only annoying, but wondering if anyone can fix?
EDIT: Screenshots added:
Gnome's System Settings:
Region & Language