The President, however, was no longer satisfied with indecision and excuses, and telegraphed to Buell on January 7:
"Please name as early a day as you safely can on or before which you can be ready to move southward in concert with Major-General Halleck. Delay is ruining us, and it is indispensable for me to have something definite. I send a like despatch to Major-General Halleck."
To this Buell made no direct reply, while Halleck answered that he had asked Buell to designate a date for a demonstration, and explained two days later: "I can make, with the gunboats and available troops, a pretty formidable demonstration, but no real attack." In point of fact, Halleck had on the previous day, January 6, written to Brigadier-General U.S. Grant: "I wish you to make a demonstration in force": and he added full details, to which Grant responded on January 8: "Your instructions of the sixth were received this morning, and immediate preparations made for carrying them out"; also adding details on his part.
Ulysses S. Grant was born on April 27, 1822, was graduated from West Point in 1843, and brevetted captain for gallant conduct in the Mexican War; but resigned from the army and was engaged with his father in a leather store at Galena, Illinois, when the Civil War broke out. Employed by the governor of Illinois a few weeks at Springfield to assist in organizing militia regiments under the President's first call, Grant wrote a letter to the War Department at Washington tendering his services, and saying: "I feel myself competent to command a regiment, if the President in his judgment should see fit to intrust one to me." For some reason, never explained, this letter remained unanswered, though the department was then and afterward in constant need of educated and experienced officers. A few weeks later, however, Governor Yates commissioned him colonel of one of the Illinois three years' regiments. From that time until the end of 1861, Grant, by constant and specially meritorious service, rose in rank to brigadier-general and to the command of the important post of Cairo, Illinois, having meanwhile, on November 7, won the battle of Belmont on the Missouri shore opposite Columbus.
The "demonstration'" ordered by Halleck was probably intended only as a passing show of activity; but it was executed by Grant, though under strict orders to "avoid a battle," with a degree of promptness and earnestness that drew after it momentous consequences. He pushed a strong reconnaissance by eight thousand men within a mile or two of Columbus, and sent three gunboats up the Tennessee River, which drew the fire of Fort Henry. The results of the combined expedition convinced Grant that a real movement in that direction was practicable, and he hastened to St. Louis to lay his plan personally before Halleck. At first that general would scarcely listen to it; but, returning to Cairo, Grant urged it again and again, and the rapidly changing military conditions soon caused Halleck to realize its importance.
Within a few days, several items of interesting information reached Halleck: that General Thomas, in eastern Kentucky, had won a victory over the rebel General Zollicoffer, capturing his fortified camp on Cumberland River, annihilating his army of over ten regiments, and fully exposing Cumberland Gap; that the Confederates were about to throw strong reinforcements into Columbus; that seven formidable Union ironclad river gunboats were ready for service; and that a rise of fourteen feet had taken place in the Tennessee River, greatly weakening the rebel batteries on that stream and the Cumberland. The advantages on the one hand, and the dangers on the other, which these reports indicated, moved Halleck to a sudden decision. When Grant, on January 28, telegraphed him: "With permission, I will take Fort Henry on the Tennessee, and establish and hold a large camp there," Halleck responded on the thirtieth: "Make your preparations to take and hold Fort Henry."
It would appear that Grant's preparations were already quite complete when he received written instructions by mail on February 1, for on the next day he started fifteen thousand men on transports, and on February 4 himself followed with seven gunboats under command of Commodore Foote. Two days later, Grant had the satisfaction of sending a double message in return: "Fort Henry is ours.... I shall take and destroy Fort Donelson on the eighth."
Fort Henry had been an easy victory. The rebel commander, convinced that he could not defend the place, had early that morning sent away his garrison of three thousand on a retreat to Fort Donelson, and simply held out during a two hours' bombardment until they could escape capture. To take Fort Donelson was a more serious enterprise. That stronghold, lying twelve miles away on the Cumberland River, was a much larger work, with a garrison of six thousand, and armed with seventeen heavy and forty-eight field guns. If Grant could have marched immediately to an attack of the combined garrisons, there would have been a chance of quick success. But the high water presented unlooked-for obstacles, and nearly a week elapsed before his army began stretching itself cautiously around the three miles of Donelson's intrenchments. During this delay, the conditions became greatly changed. When the Confederate General Albert Sidney Johnston received news that Fort Henry had fallen, he held a council at Bowling Green with his subordinate generals Hardee and Beauregard, and seeing that the Union success would, if not immediately counteracted, render both Nashville and Columbus untenable, resolved, to use his own language, "To defend Nashville at Donelson."
An immediate retreat was begun from Bowling Green to Nashville, and heavy reinforcements were ordered to the garrison of Fort Donelson. It happened, therefore, that when Grant was ready to begin his assault the Confederate garrison with its reinforcements outnumbered his entire army. To increase the discouragement, the attack by gunboats on the Cumberland River on the afternoon of February 14 was repulsed, seriously damaging two of them, and a heavy sortie from the fort threw the right of Grant's investing line into disorder. Fortunately, General Halleck at St. Louis strained all his energies to send reinforcements, and these arrived in time to restore Grant's advantage in numbers.
Serious disagreement among the Confederate commanders also hastened the fall of the place. On February 16, General Buckner, to whom the senior officers had turned over the command, proposed an armistice, and the appointment of commissioners to agree on terms of capitulation. To this Grant responded with a characteristic spirit of determination: "No terms except unconditional and immediate surrender can be accepted. I propose to move immediately upon your works." Buckner complained that the terms were ungenerous and unchivalric, but that necessity compelled him to accept them; and Grant telegraphed Halleck on February 16: "We have taken Fort Donelson, and from twelve to fifteen thousand prisoners." The senior Confederate generals, Pillow and Floyd, and a portion of the garrison had escaped by the Cumberland River during the preceding night.