

To clarify a lot of confusion I see in the comments. This book considers a country to be invaded when:
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At any point during the history of England, Whales, northern Ireland, Scotland, and or significant predecessors any army of theirs “invaded”,
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Counting any part of the land that is now considered part of the UN country. So not only from when the country existed,
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And being invaded meaning they had some control over, or fought conflicts in the territory.
Correct: https://maps.app.goo.gl/UbBhV73h7CJTAtGX6