In 1889 William F. Fox published his Regimental Losses in the American Civil War. It has become famed for listing the 300 Union units which suffered the highest casualties during the conflict, but Fox also charts the losses of those Federal formations with casualty rates outside those fabled 300. Although certain elements of the work have been revised, it still stands virtually alone as a single source for detailed Union casualty figures from the American Civil War.

Although the majority of Irishmen served in non-Irish units during the conflict, there were still a large number of ‘Irish’ regiments. The list below reproduces Fox’s figures for 21 of these regiments. Despite being interesting in and of itself, the list necessarily needs to be treated with caution. It excludes what might be regarded as non-infantry ‘Irish’ units (such as the 13th Pennsylvania Cavalry), infantry regiments that were designated as Irish but did not have large Irish numbers in the ranks (such as the 15th Maine Infantry) and infantry regiments that despite not been termed ‘Irish’ did have large Irish numbers in the ranks (such as the 42nd New York Infantry).

The 21 infantry regiments suffered a combined total of 4,808 fatalities during the American Civil War. Of these 2,277 were combat related, with a further 2,531 being due to other causes, such as illness or accident. The 69th New York of the Irish Brigade was the regiment that suffered the most fatalities, with 401 deaths. The 69th also suffered the most combat casualties, but it was the 30th Missouri that sustained the most deaths due to disease, with a staggering 280 deaths. The 9th Massachusetts and 88th New York were the most dangerous regiments to serve in as an officer, with both losing 18 officers during the conflict. Not all of the men represented by these figures were Irish, and as stated above the statistics are ultimately of somewhat limited use when studying the Irish experience of the conflict. However they do present an interesting ‘at a glance’ review of some of the more famous Irish units, and perhaps most starkly highlight the role of disease as the greatest killer of the American Civil War.

*KIA (Killed in Action), DoW (Died of Wounds), DoD (Died of Disease).

References

Fox, William F. 1889. Regimental Losses in the American Civil War 1861-1865.