Situation in 1861
At the outset of the war, Union efforts in the West were hampered by a lack of unified command. The theater was divided into three separate departments: the Department of Kansas, under Maj. Gen. David Hunter, the Department of Missouri, under Maj. Gen. Henry Halleck, and the Department of the Ohio, under Maj. Gen. Don Carlos Buell. Facing them was a single Confederate command headed by Gen. Albert Sidney Johnston. Stretching from the Cumberland Gap in the east to Arkansas in the west, Johnston was required to defend a broad front with inferior numbers and a chronic shortage of supplies.
Missouri & Kentucky
Initial movements in the West were centered on securing the border states of Missouri and Kentucky. Following a Union victory at Boonville in June 1861, Missouri was prevented from seceding. For much of the war, both Union, Confederate, and irregular forces would wrestle for control of the state. In Kentucky, the state government declared neutrality and threatened to oppose whichever side entered the state first. On September 3, Confederate Maj. Gen. Leonidas Polk crossed the border and occupied Columbus. This was countered on the 5th when Union troops under Brig. Gen. Ulysses S. Grant took Paducah. In response to these actions, Kentucky elected to remain in the Union, though it did supply troops to both sides.
After months of minor actions, Halleck authorized Grant to move up the Tennessee River and Cumberland Rivers to attack Forts Henry and Donelson. Working in conjunction with gunboats under Flag Officer Andrew H. Foote, Grant began his advance on February 2, 1862. Realizing that Fort Henry was located on a flood plain and open to naval attack, the installation's commander, Brig. Gen. Lloyd Tilghman, withdrew most of his garrison to Fort Donelson before Grant arrived on the 6th.
After occupying Fort Henry, Grant immediately moved against Fort Donelson eleven miles to the east. Situated on high, dry ground, Fort Donelson proved near invulnerable to naval bombardment. After direct assaults failed, Grant invested the fort. On the 15th, Confederate forces under Brig. Gen. John B. Floyd attempted a breakout but were contained before creating an opening. With no options left, Brig. Gen. Simon B. Buckner asked Grant for surrender terms. Grant's response was simply, "No terms except unconditional and immediate surrender can be accepted," which earned him the nickname "Unconditional Surrender" Grant. With the fall of Fort Donelson, over 12,000 Confederates were captured, nearly a third of Johnston's forces. As a result, he was forced to order the abandonment of Nashville, as well as a retreat from Columbus, KY.
Newly promoted to major general, Grant moved south along the Tennessee River to Pittsburg Landing near Shiloh Church. Upon arriving, Halleck, who had recently been given complete command of the western theater, ordered Grant to pause and wait for a second Union army under Maj. Gen. Don Carlos Buell to join him. Meanwhile, Johnston and his newly appointed second-in-command, Gen. P.G.T. Beauregard, were concentrating their forces around Corinth, MS, with the goal of striking at Grant before he was reinforced.
Moving north in early April, the two Confederate generals launched a surprise dawn attack on Grant's camps on the 6th. Striking hard, Johnston's men were able to drive back the Union troops. As Grant's men retreated, two divisions under Brig. Gens. Benjamin M. Prentiss's and W.H.L. Wallace doggedly defended an area known as the "Hornet's Nest" for close to seven hours. As the Confederate attacks focused on this area, it gave Grant time to reorganize his lines. With nightfall, the Confederates paused to regroup and deal with the loss of Johnston who had been mortally wounded in the afternoon.
During the night Grant's army was bolstered by the arrival of Buell's Army of the Ohio. Now possessing 45,000 men, Grant decided to counterattack in the morning. At dawn, Beauregard, who had been planning on finishing off Grant that day, was surprised to see the Union troops moving forward. After heavy fighting, they recaptured their original camps and forced Beauregard's army to retreat back towards Corinth. The Battle of Shiloh was the bloodiest encounter to date with the Union suffering 13,047 casualties and the Confederates 10,699. It proved a harbinger of the bloodshed that would occur later in the in war.
While Grant was fighting at Shiloh, Union troops under Maj. Gen. John Pope, with the assistance of Foote's gunboats, were assaulting Island Number 10. Located at the Kentucky bend in the Mississippi River, the Confederates had constructed numerous batteries to impede the Union advance down the river. After naval bombardment and having their escape route severed by Pope's men, the garrison surrendered on April 8. The capture of Island Number 10 led to the fall of Memphis two months later.
To the south, the US Navy was beginning operations against the Confederacy's largest seaport, New Orleans. Commanded by Flag Officer David G. Farragut, ships of the West Gulf Blockading Squadron attacked and ran past Forts Jackson and St. Philip south of the city on April 24. They anchored off the city the following day and accepted its surrender. On May 1, Union troops under Maj. Gen. Benjamin Butler entered the city and established a military government. With Union forces occupying both Memphis and New Orleans, the control of the Mississippi River was nearly complete.Previous: War in the East, 1862-1863 | Civil War 101 | Next: Turning Points