The Irish had 140,000 volunteers in WW1. Many of them from what is now Eire. 35,000 of them were killed. I do not have the statistics of those crippled and lost limbs in that horrible carnage. There must have been a large number.
Though I cannot claim to be of Irish descent, my great grandfather was born in County Cork of two English parents 1834.
In WWI Ireland wasn’t independent; when Round II started in 1939, they were - and promptly sat it out.
England at this point is stuck with a welfare state in the north (as the industry has died), which their transplanted subjects (moved there over the centuries to solidify their claim to it) refuse to abandon - and demand to be maintained there on the dole.