alt Hacker News> Ireland dislikes the UK since the UK invaded it
This was centuries before the UK. The Normans came to Ireland by invitation of Macmurphy, King of Leinster, to help him restore his power, in exchange for promises of territory. This barely counts as a conquest CB, but with certainty not as an invasion.
The Tudor conquest of Ireland involved the English and Scottish. It was before the UK existed, but was perpetrated by the constituents of the UK. At least, the ancestors of the contemporary constituents. Maybe not of Wales though, I don't know.