Northern Ireland is one of the four entities that make up the sovereign nation of the United Kingdom. A common misconception is that it is a country; while England, Scotland and Wales are constituent countries (not sovereign nations) within the UK, Northern Ireland is actually only a province and has never been a country in its own right.
I think it might be because it isnt one word. You dont tend to think about words like new north and south.
The B quiz does so for Myanmar.
The M one does so for Micronesia (although, interestingly, not Myanmar).
See also the P quiz and Palestine.
[Note: I don't think that it's necessary for the Netherlands even though the issue does arise there too.]
MY DAD IS FROM NIGERIA ARE YOU KIDDING ME
i actually started banging my head on the table and now i have a hickey Q_Q
"northkorea, nz, holland, macedonia".
nicaragua, niger, nigeria, nepal, namibia, norway and nauru stay the same
And North korea