The Republic of Ireland (the west most region on the first page) isn't part of the United Kingdom. The term for the group of regions shown is 'the British Isles'. See https://qntm.org/uk While it seems like a trivial distinction the whole thing is somewhat fraught (https://en.wikipedia.org/wiki/The_Troubles).
It's about as "trivial" a distinction as considering Crimea (or the entirety of Ukraine, for that matter) a part of Russia.
Many, many people have died for this triviality.
"Somewhat fraught" is a very interesting choice of words, but then again, so is "The Troubles" (when the subject matter is decades of bombings and killings).
I prefer the term “Atlantic Archipelago”. The “British Isles” encompassing a non-british sovereign state is contentious. Other good terms are “Britain and Ireland” or the “British-Irish isles”
Many, many people have died for this triviality.
"Somewhat fraught" is a very interesting choice of words, but then again, so is "The Troubles" (when the subject matter is decades of bombings and killings).