Since the outbreak of the war, Nashville had been converted into a huge arsenal and depot of supplies. Large quantities of food, clothing, and munitions had been collected and stored in its warehouses. Its factories were turning out percussion caps, sabers, muskets, saddles, harness, knapsacks, cannon, and rifled pieces. Its looms were turning out thousands of yards of gray cloth which were being made into uniforms for the soldiers. The loss of this city would be an irreparable blow to the Confederacy. [Illustration: _The_ WAR IN THE WEST _before Shiloh_] While General Johnston was establishing his positions, the Federals were rapidly organizing their forces preparatory to an attack upon the Confederate line. Gen. Henry W. Halleck, from headquarters in St. Louis, was strengthening his positions at Cairo, Ill., and Paducah, Ky. At the same time, he was making ready a large number of river steamers so that his troops could be moved by water to almost any point along his front. From headquarters in Louisville, Gen. Don Carlos Buell, commander of the Department of the Ohio, reinforced his line so that Johnston had to keep his main force at Bowling Green, Ky., to guard the important railroads which penetrated Middle and West Tennessee. [Illustration: _Commodore Foote’s gunboats ascending the Tennessee to attack Fort Henry._] Various plans for an attack upon the Confederate line were considered by the Federals. General Halleck, commander of the Department of the Missouri, believed that it would take an army of not less than 60,000 men, under one commander, to break the well-established line. He, therefore, asked that General Buell’s army be transferred to him, or at least placed under his command. Before a union of the two departments could be effected, General Grant asked for, and received, permission to attack the line at Fort Henry. A combined land and naval attack by Grant’s troops and the gunboat fleet of Commodore Andrew H. Foote resulted in the surrender of Fort Henry on February 6, 1862, and the capture of Fort Donelson, with about 12,000 prisoners, on the 16th. The loss of these forts broke Johnston’s line at its center and compelled him to evacuate Bowling Green and Columbus, permitting western Kentucky to fall into Union hands. To prevent encirclement, he was also forced to withdraw from Nashville, abandon Middle and West Tennessee, and seek a new line on the Memphis and Charleston Railroad. Following the fall of Forts Henry and Donelson, Grant incurred the displeasure of General Halleck by sending a division of troops into Buell’s department at Clarksville. Halleck’s indignation increased when he learned that Grant had gone to Nashville for consultation with Buell. Halleck directed the withdrawal of the division from Clarksville, suspended Grant from command, and ordered him to Fort Henry to await orders.