William F. Fox, Lt. Col. U. S. V., Regimental Losses in the American Civil War, 1861-1865: A Treatise on the extent and nature of the mortuary losses in the Union regiments, with full and exhaustive statistics compiled from the official records on file in the state military bureaus and at Washington

It may be of interest to state here that on the records of the War Department some of these regiments are not credited with quite so many men killed; and, that if a tabulation were to be made from the official figures at Washington, the relative positions of some of these regiments would have to be slightly changed. In the first five regiments the Seventh Wisconsin would head the list, and the Fifth New Hampshire would stand third instead of first; while the Eighty-third Pennsylvania, the Fifth Michigan and the Twentieth Massachusetts would still hold, respectively, the second, fourth and fifth places, as before. The records of the War Department show as follows:

This difference arises from the fact that in each regiment there were men borne on the muster-out rolls as “missing in action,” whose fate had not been determined at the close of the war, at which time these rolls were made out. But, since then, many of the States have made strenuous efforts to ascertain the fate of these men. New Hampshire, for instance, published a supplement to its printed muster-out rolls, in which it accounts definitely for most of its missing, the State Adjutant-General having obtained, from various sources, satisfactory evidence that these men were killed. But the War Department declines — and very properly — to to account for missing men as killed until they receive official information to that effect. The official channels, through which such information must come, are the original records of the muster-out rolls; the final statements, as they are technically termed; and the affidavits which may accompany a pension claim.

Now, the State of New Hampshire, and other States as well, have ascertained definitely that many of their missing men werekilled, and have revised their records accordingly;¹ but, if these missing men have no heirs to prosecute their claims at the Pension Office, the records at Washington will remain unchanged and the men will still be recorded there, not among the killed, but as missing. The mortuary statistics in these pages are compiled largely from State records; hence, the figures in many cases will exceed those of the War Office. The variation, however, is not important enough to warrant this digression were it not for the honest endeavor to arrive at exactness, and to forestall any possible misunderstanding or controversy.

In treating here of the matter of losses in battle, or otherwise, each regiment will be considered by itself. Hence, it is important that the student before going further should understand thoroughly the size and formation of a regiment, in order to comprehend the extent and nature of the loss. Otherwise, the figures would have little or no meaning.

The infantry regiments, which formed the bulk of the army, had a maximum of organization beyond which recruiting was not allowed. There was, also, a minimum of strength which must be obtained before a regiment could be accepted. An infantry command consisted of ten companies of foot, and the Field and Staff : the latter were mounted, and consisted of the Colonel and such officers as were not attached to the company formations. The maximum formation was as follows;