Tongue in cheek, Irish settlers go to South America, they colonise a large chunk of Argentina (they did arrive in large numbers in RL) the whole Falklands thing happens early 20th century, Argentina wins, becomes most powerful state in SA, decide to free the mother country, invade, the Brits are busy with WW1, Ireland liberated, union with Argentina, side with the Germans, WW1 ends in pretty much stalemate,
Brit's don't loose but don't win either, New Hibernian union decides that some land aquistion of it's own is in order, takes Uraguay, part's of Chile, Peru ect, weakend UK Scotland decides on independence, large numbers of Irish/Scots want union, ethnically cleanse Scotland, union, now named the Gaelic union, war with Colombia, union wins annexes the country, Brazil signs non aggression pact, large art's of Canada with dominient Irish/Scots populations vote to leave and join union, non aggresion and friendship pact with the US, encourage insurrection in Australia and NZ, GU attempts first manned moon landing, pilot drunk ship crashes, pilot refuses to be breathalized, insurence on ship null and void, many people annoyed, GU invades rump English state, resistence collapses due to the huge amount of Irish and Scottish people keeping the construction industry and pubs going refuse to work and join in an insurrection, the World desends into 1000 years of peace and contentment under the benevolent rule of the Celts.....