I know this is a bit off topic and before I start im making it known im Irish, and not some paddy-whacker

Imaging if the 1798 rebellion had suceeded? With French help of course...
Imagine what that would have done for the entire Napoleonic wars? If Napoleon had a base to invade England with, we could all be speaking French today (Obviously the Empire would have collapsed at some stage, history shows us that sustaining an Empire of hundreds of years just isnt possible.)
I have to say, I think
on the whole it was better that the rebellion was a failure - if it had suceeded without French help it would be a different story.
So I suppose you could say Ireland had a pivotal role in the Napoleonic wars (1798 may be out of N:TW's timeframe), more on a geographical sense than from a view of "what British/French units were Irish".