In the real world the UK is still a combination of four different countries, despite the fact that there are political groups out there who would very much like to separate Northern Ireland, Wales, and Scotland from England.
In fiction things are very different, and the Marvel Cinematic Universe is no exception because it seems as though Wales is an independent country.
The latest instalment of the MCU, Black Panther, finishes off with two post credit scenes, the first of which features T'Challa setting up his contractually obligated sequel and addressing the UN to reveal Wakanda's rich technology to the world.
What some people noticed, however, is that one of the UN flags featured in this scene belongs to Wales.
— geeksarecool (@geeksarecool) February 16, 2018
The UN doesn't include individual flags for each of the UK's constituent countries, so that implies Wales is actually independent within Marvel's on-screen franchise.