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

Chapter 3: percentage of killed in regiments in particular battles — comparison of such losses with those of European regiments.

In proportion to the number engaged, the greatest loss sustained by any regiment, during the war, was that of the First Minnesota at Gettysburg. This regiment was then in Harrow's Brigade, Gibbon's Division, Second Corps. On the afternoon of the second day at Gettysburg, the Union line was driven back in confusion from its position along the Emmettsburg road. While Hancock was “patching” up a second line, he perceived a column of the enemy (Willcox's Brigade) emerging suddenly from a clump of trees near an unprotected portion of his line. The First Minnesota, alone and unsupported, was in position near by, and Hancock, desirous of gaining time until reenforcements could be brought forward, rode up to Colonel Colville and ordered him to take the enemy's colors.¹ A desperate fight ensued, in which the enemy was forced back, leaving their colors in the hands of the First Minnesota. Speaking of this affair afterwards, General Hancock is reported to have said:

There is no more gallant deed recorded in history. I ordered those men in there because I saw that I must gain five minutes time. Reenforcements were coming on the run, but I knew that before they could reach the threatened point the Confederates, unless checked, would seize the position. I would have ordered that regiment in if I had known every man would be killed. It had to be done, and I was glad to find such a gallant body of men at hand, willing to make the terrible sacrifice that the occasion demanded.

The regiment took 262 officers and men into this affair.² It lost 50 killed and 174 wounded, total, 224 casualties, nearly all of which occurred in this fight. A remarkable feature of this loss is that none were missing. Seventeen officers were killed or wounded, [27] the latter including the Colonel, Lieutenant Colonel, Major, and Adjutant. The killed, with those who died of their wounds, numbered 75, or over 28 per cent. of those engaged — a percentage of killed unequalled in military statistics.³

The next largest percentage of killed occurred at Spotsylvania, in the Fifteenth New Jersey. This regiment belonged to the First Jersey Brigade, Wright's Division, Sixth Corps, and lost 116 killed or mortally wounded at Spotsylvania. Unlike the sudden loss of the First Minnesota at Gettysburg, its casualties occurred in three different actions: 31 were lost on May 8th, 5 on May 10th, and 80 on May 12th, at the Bloody Angle. It may be urged that, these being three different affairs, the losses should not be consolidated. If they had occurred at different places, as, for instance, South Mountain and Antietam, the criticism would hold good; but this fighting was done at one place, and the continuous nervous strain made it as heroic as if the lose had occurred in one brief charge. This regiment crossed the Rapidan May 5th, with 444 effective men.⁴ It sustained but a slight loss at the Wilderness, and took 432 officers and men into action at Spotsylvania, of whom 116 were killed or died of wounds — a loss of 26 per cent. Within nine days after breaking camp, it was reduced to 5 officers and 136 men available for action.

Next, in percentage of killed in particular engagements, is the Twenty-fifth Massachusetts at Cold Harbor, then in Stannard's Brigade, Martindale's Division, Eighteenth Corps. This loss occurred in the assault on the earthworks at Cold Harbor, where it was subjected to a terrible fire. A Confederate officer, describing the advance of the Twenty-fifth against his works, writes that the heroic regiment struggled forward under a fire which seemed to literally annihilate them; that the whole line seemed to disappear; and he expresses wonder that any could have survived. The loss was 53 killed, 139 wounded, and 28 missing, “out of 310 reported for duty that morning.” ⁵ On the following day there were only 4 officers and 62 men left on duty. Many of the missing were killed. The muster-out rolls of the Twenty-fifth bear the names of 74 officers and men who were killed or mortally wounded during the quarter of an hour which covered that assault; a loss of 24 per cent. in killed, and over two-thirds in killed and wounded. The small number taken into this action was owing to the heavy losses which the regiment had just sustained, a few days previous, in the Drewry's Bluff campaign. The Confederate officer just referred to, states further that his men were massed five ranks deep behind their breastworks; that the front rank alone fired, while the others passed up loaded rifles, which were discharged as rapidly as they could be fired; that, in addition to this, the artillery posted in the salients, poured a flanking fire of canister into the ranks of the doomed regiment.

A smaller loss as to the number killed, but equally remarkable as to percentage, is found in the record of the One Hundred and Forth-first Pennsylvania at Gettysburg. This regiment was, at that time, in Graham's Brigade, Birney's Division, Third Corps. It had already lost at Chancellorsville 235 (killed, wounded, and missing) out of 417 engaged there. At Gettysburg, only 198 answered to the morning roll call,⁶ of whom 25 were killed, 103 wounded, and 21 missing; total, 149. The killed, with those who died of wounds, numbered 49, or 24 per cent. of those engaged. The one Hundred and Forty-first fought at Gettysburg in the famous Peach Orchard.

One of the most remarkable losses in the war, both in numbers and percentage, occurred at Manassas, in Gen. Fitz John Porter's Corps, in the celebrated Duryee Zouaves (Fifth New York), of Warren's Brigade, Sykes' Division. General Sykes, in his official report, states [28] that the regiment took 490 into action. It lost 79 killed, 170 wounded, and 48 missing; total, 297. Many of the missing were killed. The deaths from wounds increased the number killed to 117,⁷ or 23 per cent. of those engaged, the greatest loss of life in any infantry regiment during the war, in any one battle. The regiment held an exposed position, and Gen. Warren states that when he endeavored to extricate them, “they were unwilling to make backward movement.” This is the regiment which, at Gaines' Mill, having been badly thinned, closed up its ranks and counted off anew “with great coolness while exposed to a most terrific fire!” --(Official Report.)

The following list of percentages will indicate fairly the extent of loss in killed, to which a regiment is liable in battle. The number engaged is, in most cases, taken from the official reports. In some instances, however, the number given was ascertained firom statements in regimental histories.

Percentages of killed in regiments, in particular engagements.