Wrote Gen. G. W. Cullum, Chief of Staff, Dept. of the Mo. “I am pleased to announce to you the unconditional surrender this morning of Fort Donelson, with twelve to fifteen thousand prisoners, at least forty pieces of Artillery and a large amount of stores, horses, mules and other public property. I left Fort Henry on the 12th inst. with a force of about 15000 men, divided into two Divisions under the commands of Gens. McClernand and Smith. Six regiments were sent around by water the day before, convoyed by a gun boat, or rather started one day later than one of the gunboats, and with instructions not to pass it.
“The troops made the march in good order, the head of the column arriving within two miles of the Fort, at 12 o’clock M. At this point the enemies’ pickets were met and driven in.
“The fortifications of the enemy were from this point gradually approached and surrounded with occasional skirmishing on the line. The following day, owing to the non-arrival of the Gunboats and reinforcements sent by water, no attack was made, but the investment was extended on the flanks of the enemy and drawn closer to his works, with skirmishing all day. The evening of the 13th, the Gunboats and reinforcements arrived. On the 14th, a gallant attack was made by Flag Officer Foote, upon the enemies’ works, with his fleet. The engagement lasted probably one hour and a half and bid fair to result favorably to the cause of the Union when two unlucky shots disabled two of the Armoured boats so that they were carried back by the tide. The remaining two were very much disabled, also having received a number of heavy shots about the pilot houses and other parts of the vessels.
“After these mishaps I concluded to make the investment of Fort Donelson as perfect as possible and partially fortify and await repairs to the gunboats. This plan was frustrated however by the enemy making a most vigorous attack upon our right wing, commanded by Gen. J. A. McClernand, with a portion of the force under Gen. L. Wallace. The enemy were repelled after a closely contested battle of several hours in which our loss was heavy. The officers, and particularly field officers, suffered out of proportion. I have not the means yet of determining our loss even approximately, but it cannot fall far short of 1200 killed, wounded and missing. Of the latter I understand through Gen. Buckner about 250 were taken prisoners. — I shall retain enough of the enemy to exchange for them as they were immediately shipped off and not left for recapture. — About the close of this action, the ammunition in cartridge boxes gave out, which with the loss of many of the Field officers produced great confusion in the ranks. Seeing that the enemy did not take advantage of it convinced me that equal confusion, and possibly great demoralization, existed with him. Taking advantage of this fact I ordered a charge upon the left, — Enemy’s right — with the Division under Gen. C. F. Smith which was most brilliantly executed and gave to our arms full assurance of victory. The battle lasted until dark, giving us possession of part of the entrenchments. — An attack was ordered from the other flank, after the charge by Gen. Smith was commenced, by the Divisions under Gens. McClernand and Wallace, which, notwithstanding the hours of exposure to a heavy fire in the fore part of the day, was gallantly made and the enemy futher repulsed.
“At the points thus gained, night having come on, all the troops encamped for the night feeling that a complete victory would crown their labors at an early hour in the morning.
“This morning at a very early hour a note was received from Gen. S. B. Buckner, under a flag of truce, proposing an armistice etc. A copy of the correspondence which ensued is herewith accompanying.”
The Papers of Ulysses S Grant, Vol 4, p 222-225
O.R., I, vii, 159-60