>>17846074 (OP)British - term for the various peoples that make up the Isles, English, Scots, Welsh, Kerns, Manx, Irish (depends who you ask lol).
English - Culturally Germanic, but still over 50% Celtic by blood in most places, dominant power in Britain for over 1,000 years even before called England after invasions.
Celtic - term come up with fairly recently to define the peoples that weren't Germanic and were dominant culturally over much of Europe, but now pushed back to small areas, still make up the majority of blood for people around the Isles.
Scottish - in three varieties: Lowlander (much more culturally and racially Germanic then the others but like to LARP as 100% true Celts, dominant in Scotland), Highlander (Celtic, fucked over by land reform), Islander (Norse-Gaels, combo of Celtic and Norse from being a Viking Kingdom for ages, last place to lose the Celtic language, ironic as is known as "Land of the foreigners" in Gallic)
Irish - abound with butt hurt because the English used them as a punching bag when they refused to go Protestant with everyone else. Up until the Reformation they were treated by the Anglo-Norman and then English state with the same shittbaggery the state always does, even to its own people, but the bad feeling stayed in Ireland unlike Scotland and Wales because sectarianism, still going to this day because King James wisely decided the Irish were going to be continual pains because Catholic so planted a colony of Protestant Scots (Ulster) in the North.
