The investment of Nashville was raised by General Rosecrans, who had succeeded General Buell in command of the Army of the Cumberland, after defeating and routing at Corinth the rebel force which, under Van Dorn and Price, had attempted the invasion of West Tennessee and Kentucky.
In the last days of the year 1862 the Army of the Cumberland moved from Nashville upon the position of Murfreesborough, and here an obstinately contested battle was fought, which resulted, after great loss on both sides, in the retreat of the insureants and the occupation of Murfreesborough by the forces of the Union. A long period of rest, devoted on both sides to efforts to increase the strength and efficiency of the armies, ensued. Frequent skirmishers, cavalry expeditions to destroy communications, in which both armies showed enterprise, courage, and a gradual improvement in efficiency and soldierly skill, filled up the time on the borders of Tennessee, Kentucky, Mississippi, and Alabama.
The reduction of Vicksburg presented unexpected difficulties. General Grant, the commander of the Department and of the Army of the Tennessee, finally took command of the troops investing that stronghold.
The naval squadron in the Mississippi was steadily increased in strength until over 100 armed vessels were destroyed upon the river, many of them iron-clad gun-boats of great power.
Attempts were made to repeat the operation successful at Island Numbers 10, but the canal project and executed failed to change the channel of the river, and expeditions were set on foot to turn the enemy's position by some of the bayous and rivers which form so singular a feature of the military topography of the Mississippi and its banks.
All these failing, General Grant and Admiral Porter sent steamers to run the gauntlet of the batteries at Vicksburg, Warrenton, and Grand Gulf, and, marching the army down the right bank, ferried it across the great river by means of the transport steamers which had safely made the dangerous passage.
The batteries of Grand Gulf, after resisting a heavy bombardment from the fleet at short range, were abandoned as soon as General Grant's army march to their rear. By a series of brilliant maneuvers, marching and fighting day by day, General Grant succeeded in separating the rebel armies, beating Johnston and driving him out of the city of Jackson, the capital of Mississippi.
Numerous combats, in all of which the loyal armies were successful, resulted in the division of the army of General Pemberton, a portion under General Loring being cut off and driven to the southeast, while Pemberton himself, with over 30,000 soldiers, was shut up within the lines of Vicksburg. The batteries near the month of the Yazoo, abandoned by the enemy, fell into the hands of Admiral Porter and were destroyed, and a detachment of his fleet ascended that river and destroyed vessels and stores of the enemy.
General Grant, who had during these brilliant operations abandoned his communication, closely invested the city, re- established his connection with the fleet of gun-boats and transports, both above and below the city, and ignorant of the numbers inclosed within its works, tried an assault. It was unsuccessful, and he sat down to reduce it by the less bloody, but surer, method of siege.
A gallant defense was made by Pemberton, hoping for relief from Johnston. Strenuous efforts were made by the insurgent chiefs to