(1) Not one, but two, separate areas of military operations existed. The Appalachian Mountains, extending in an almost unbroken line from Pennsylvania to Alabama, prevented armies from moving freely from eastern states (Virginia, the Carolinas, etc.) to western or trans-Appalachian states (Tennessee, Kentucky, etc.), and vice versa. As a result, different armies in the East (east of the mountains) and in the West fought practically two almost independent wars. Only in 1864 were the campaigns of the two areas effectively coordinated.
(2) In the 1800’s, in contrast to modern military tactics, an invading army did not always move directly against an enemy force. Rather, its primary target was usually an important city. Once the invading army was in motion, the defending force then tried to place itself between the invader and his target. This set the stage for battle. Five such Confederate cities became principal Federal targets. In the East was Richmond; in the West were New Orleans and Vicksburg, both strongholds on the all-important Mississippi River, and Chattanooga and Atlanta, vital railroad centers.
Bearing these two points in mind, let us turn to the Western campaigns of 1862.
At the beginning of 1862 some 48,000 Confederate soldiers guarded a 600-mile line extending from the Appalachian Mountains westward to the Mississippi River. Obviously the Southern defenses were thinly manned. Early in February, Gen. Ulysses S. Grant left Cairo, Ill., with 15,000 men to attack the center of this line. His goal was to gain control of two important rivers, the Tennessee and the Cumberland.
To protect these streams, the Confederates had constructed twin forts in Tennessee just south of the Kentucky border. Fort Henry guarded the Tennessee; Fort Donelson stood menacingly on the banks of the Cumberland. On February 6 a Federal river fleet cooperating with Grant battered Fort Henry into submission. Ten days later Grant had surrounded Fort Donelson and its 12,000 defenders. Answering the Confederate commander’s request for surrender terms, Grant replied: “No terms but unconditional surrender.” Thereafter, U. S. Grant was “Unconditional Surrender” Grant.
Grant’s victories brought great rejoicing in the North. Some writers consider the Henry-Donelson campaign as “the critical operation” of the Civil War. Capture of these forts assured Union control of Kentucky and Tennessee and opened Mississippi and Alabama to Federal invasion. The loss of the forts was a severe blow to Southern morale. With these successes the North had also demonstrated its ability and willingness to fight.
Meanwhile, an important battle occurred farther to the west for control of Arkansas and Missouri. On March 7-8, at Pea Ridge (or Elkhorn Tavern), Ark., a Confederate army of 16,000 men attacked 12,000 Federals under Gen. Samuel R. Curtis. Most of the Confederates lacked uniforms and were armed with shotguns and squirrel rifles. This force also included 3,500 Indians of the Creek, Choctaw, Cherokee, Chickasaw and Seminole tribes. After two days of fighting, a Federal counterattack broke the Confederate “army.” With the defeat at Pea Ridge the Confederates permanently lost Missouri and northern Arkansas.
Gunfire and fighting at Shiloh was so intense that one area of the battlefield became known as the “Hornet’s Nest.” This drawing depicts the stubborn resistance of two Federal divisions in that area.