Macha parent
The proportion of Irish Americans among the American working class in the the era of the American civil war _was_ much larger than it is today.
No doubt that is true but it doesn't seem to account for the discrepancy, at least not without acquiring more data.
Google's LLM is spitting out ~250K immigrant and first-generation Irish fighting in the Civil War, sitting roughly at 10% of the total.
That doesn't account for second-generation and older, so I would be interested to see what social mobility was like for those more-established Irish-Americans: were they languishing in the working class, or did they exit from the middle class to go fight in wars disproportionately?
edit: how significant is the class factor, anyway? Does that model really apply, and how many citizens would be considered middle or upper class; enough to make a large statistical impact?
Google's LLM is an LLM. Results from an LLM are garbage unless you can test them. Any other sources?
Yes, I made sure to highlight that this was the (unreliable) source, consider it an invitation for the history buffs to chime in.
Food for thought: if I had posted the very first source available on Google as authorative, with no actual knowledge of my own to make the claim, that could be more misleading on aggregate, right?