1864 battle of the American Civil War
The Battle of Atlanta took place during the Atlanta Campaign of the American Civil War on July 22, 1864, just southeast of Atlanta, Georgia. Continuing their summer campaign to seize the important rail and supply hub of Atlanta, Union forces commanded by William Tecumseh Sherman overwhelmed and defeated Confederate forces defending the city under John Bell Hood. Union Major General James B. McPherson was killed during the battle, the second-highest-ranking Union officer killed in action during the war. Despite the implication of finality in its name, the battle occurred midway through the Atlanta campaign, and the city did not fall until September 2, 1864, after a Union siege and various attempts to seize railroads and supply lines leading to Atlanta. After taking the city, Sherman's troops headed south-southeastward toward Milledgeville, the state capital, and on to Savannah with the March to the Sea.
The fall of Atlanta was especially noteworthy for its political ramifications. In the 1864 election, former Union General George B. McClellan, a Democrat, ran against President Lincoln, although he repudiated his own party's platform, calling for an armistice with the Confederacy. The capture of Atlanta and Hood's burning of military facilities as he evacuated were extensively covered by Northern newspapers, significantly boosting Northern morale, and Lincoln was re-elected by a significant margin.
Background.
Objectives and preparations.
War weariness was growing in the North and President Abraham Lincoln's prospects for re-election were diminishing as a result, when on March 9, 1864, Lincoln commissioned Ulysses S. Grant as the only Union Army lieutenant general, then the highest grade in the United States Army. On March 10, Lincoln gave Grant command of all the armies of the United States. On March 12, Grant's appointment as general-in-chief was publicly announced. Major General William T. Sherman was assigned to command the Military Division of the Mississippi, including the Department of the Ohio, Department of the Cumberland, Department of the Tennessee and the Department of Arkansas. Sherman took command on March 18. The assignment made Sherman commander of the Union armies in the Western theater of the war.
Grant devised a strategy for Union victory through simultaneous campaigns against several Confederate armies. Grant wanted to prevent Confederate armies from reinforcing each other in turn and to fatally weaken the entire Confederate Army. Sherman would lead one of two key campaigns. The objective of Sherman's campaign was to defeat and disperse the Confederate Army of Tennessee under the command of General Joseph E. Johnston, to capture the vital railway center of Atlanta, Georgia, to destroy or damage Confederate war resources as much as possible and to split the Confederacy again as had been done at Vicksburg, Mississippi, and Port Hudson, Louisiana, in July 1863.
On May 4, 1864, Sherman was ready to move his armies from Chattanooga, Tennessee, toward Ringgold, Georgia, with an estimated strength of 112,000 troops. Johnston had between 60,000 and 70,000 effective troops. Johnston had taken advantage of the terrain of woods, hills and rivers in northern Georgia by entrenching his army at Dalton, Georgia, about one-quarter of the way between Chattanooga and Atlanta. Historian Allan Nevins wrote that Sherman's numerical advantage did not make Johnston's position hopeless in view of his fortified line of defenses in the rough, confusing, mountainous, wooded country of northwestern Georgia which had poor roads and three difficult rivers to cross. Because Sherman had to keep his Western and Atlantic Railroad supply line open, he could break away from it only for short periods of time.
Prelude.
During the months leading up to the battle, Confederate General Joseph E. Johnston had repeatedly retreated from Sherman's superior force. All along the Western and Atlantic Railroad line, from Chattanooga, Tennessee, to Marietta, Georgia, a pattern was played and replayed: Johnston took up a defensive position, Sherman marched to outflank the Confederate defenses, and Johnston retreated again. After Johnston's withdrawal following the Battle of Resaca, the two armies clashed again at the Battle of Kennesaw Mountain, but the Confederate senior leadership in Richmond was unhappy with Johnston's perceived reluctance to fight the Union army, even though he had little chance of winning. Thus, on July 17, as he was preparing for the Battle of Peachtree Creek, Johnston was relieved of his command and replaced by Lieutenant General John Bell Hood. The dismissal and replacement of Johnston remains one of the most controversial decisions of the Civil War. Hood, who was fond of taking risks, lashed out at Sherman's army at Peachtree Creek, but the attack failed, with more than 2500 Confederate casualties.
Hood needed to defend the city of Atlanta, which was an important rail hub and industrial center for the Confederacy, but his army was small in comparison to the armies that Sherman commanded. He decided to withdraw, classically threatening Sherman's supply lines in his army's rear. Hood hoped his aggressiveness and the size of his still formidable force on-the-move would entice the Union troops to come forward against him, if only to protect their rear supply lines. The Union did not do so. McPherson's army closed in upon Decatur, Georgia, to the east side of Atlanta.
Opposing forces.
Sherman's forces in the Atlanta campaign included three armies: the Army of the Tennessee under Major General James B. McPherson (until he was killed at the Battle of Atlanta); the Army of the Cumberland under Major General George H. Thomas and the small Army of the Ohio (including only the XXIII Corps and a few small units) under Major General John M. Schofield. After McPherson's death, the Army of the Tennessee was commanded at the Battle of Atlanta by Major General John A. Logan The Army of the Tennessee comprised the XV Corps initially under the command of Logan, then under the command of Brigadier General Morgan L. Smith; the XVI Corps under the command of Major General Grenville M. Dodge, and the XVII Corps under the command of Major General Frank P. Blair Jr.
The Confederate Army of Tennessee was commanded by General Joseph E. Johnston until July 17, 1864, when he was replaced by Lieutenant General John Bell Hood. At the start of the campaign, the Army of Tennessee comprised three infantry corps under the command Lieutenant Generals William J. Hardee, Leonidas Polk and John Bell Hood, and a cavalry corps under Major General Joseph Wheeler. After Polk was killed on June 14, he was replaced in corps command by Major General William Wing Loring temporarily and on July 7 by Lieutenant General Alexander P. Stewart.
Many, but not all, of the units of both armies fought in the Battle of Atlanta and related action at Decatur on July 22, 1864.
Battle.
Hood ordered Lieutenant General William J. Hardee's corps on a march around the Union left flank, had Major General Joseph Wheeler's cavalry march near Sherman's supply line, and had Major General Benjamin Cheatham's corps attack the Union front. However, it took longer than expected for Hardee to get his men into position. Confederate Major General William H. T. Walker was killed—shot from his horse by a Union sharpshooter as he scouted the front to prepare his forces for the beginning of the battle. During the time that Hardee's corps was deploying for an attack, McPherson had correctly deduced a possible threat to his left flank. He sent XVI Corps, his reserve, to help strengthen the position. Hardee's men met this other force, and the battle began. About this time, McPherson rode to the front with two aides to determine the situation and redeploy some regiments as gunfire continued to build to the south of his line. While on this reconnaissance, McPherson was shot and killed by Confederate infantry unexpectedly moving forward. When the Confederates called on him to halt, he turned his horse and tried to escape after refusing a demand to surrender.
Although the initial Confederate attack was repulsed, the Union left flank began to retreat under heavy pressure. Initially, Hardee's column took the Flat Shoals Road toward McPherson's position. Union troops under Brigadier General Mortimer D. Leggett, commanding the 3rd Division of the XVII Corps moved back from the road and swung to a more east- west position to fill a gap between Blair's corp and Dodge's corp and defend Bald Hill. The main lines of battle now formed an "L" shape, with Hardee's attack forming the lower part of the "L," and Cheatham's attack on the Union front as the vertical member of the "L". Hood intended to attack the Union troops from both east and west. The fighting centered on a hill east of the city known as Bald Hill. The Federals had arrived two days earlier, and began to shell the city proper, killing several civilians. A savage struggle, sometimes hand-to-hand, developed around the hill, lasting until just after dark. The Federals held the hill while the Confederates retired to a point just south of there.
Meanwhile, two miles to the north, Cheatham's troops had broken through the Union lines at the Georgia railroad. In response, twenty artillery pieces were positioned on a small knoll near Sherman's headquarters and shelled the Confederates, while Logan's XV Corps regrouped and repulsed the Southern troops.
In a separate action near Decatur, Colonel John W. Sprague, in command of the 2nd Brigade, 4th Division of the XVI Corps, was attacked by Wheeler's cavalry. Wheeler had taken the Fayetteville Road and moved into the town of Decatur. Union troops fell back from the town while successfully protecting the ordnance and supply trains of the XV, XVI, XVII, and XX corps. Sprague received some reinforcements but Wheeler withdrew due to being recalled by Hardee three times in quick succession at about 5:00 p.m. to help in Hardee's attack on Bald Hill. Sprague was later awarded the Medal of Honor for his actions.
The Union had suffered over 3,700 casualties, including Major General McPherson, while the Confederate casualties numbered about 5,500. This was a heavy loss for the already reduced Confederate Army, but they still held the city.
Aftermath.
Sherman settled into a siege of Atlanta, shelling the city and sending raids west and south of the city to cut off the supply lines from Macon, Georgia. Both of Sherman's cavalry raids including McCook's raid and Stoneman's Raid 
were defeated by Confederate cavalry collectively under General Wheeler. Although the raids partially achieved their objective of cutting railroad tracks and destroying supply wagons, they were soon after repaired and supplies continued to move to the city of Atlanta. Following the failure to break the Confederates' hold on the city, Sherman began to employ a new strategy. He swung his entire army in a broad flanking maneuver to the west. Finally, on August 31, at Jonesborough, Georgia, Sherman's army captured the railroad track from Macon, pushing the Confederates to Lovejoy's Station. With his supply lines fully severed, Hood pulled his troops out of Atlanta the next day, September 1, destroying supply depots as he left to prevent them from falling into Union hands. He also set fire to eighty-one loaded ammunition cars, which led to a conflagration watched by hundreds.
On September 2, Mayor James Calhoun, along with a committee of Union-leaning citizens including William Markham, Jonathan Norcross, and Edward Rawson, met a captain on the staff of Major General Henry W. Slocum, and surrendered the city, asking for "protection to non-combatants and private property". Sherman, who was in Jonesboro at the time of surrender, sent a telegram to Washington on September 3, reading, "Atlanta is ours, and fairly won".
Within a week of the fall of Atlanta, Sherman had ordered all non-military personnel out of Atlanta. Reportedly he remembered the cities of Memphis and Vicksburg which became a burden immediately after victory, so he told the civilians specifically to go north or go south. A truce of sorts was quickly established at a town nearby called Rough And Ready with General Hood, where Union and Confederate prisoners were in small numbers exchanged and civilians wishing to go south could get help to that end. After the battle, Sherman established his headquarters in Atlanta on September 7. He stayed until November 15 when the Army of the Tennessee, then commanded by Major General Oliver O. Howard and consisting of two corps and the newly formed Army of Georgia, commanded by Major General Henry W. Slocum, also with two corps, departed for Savannah on the campaign known as "Sherman's March to the Sea".
Despite the damage caused