- First Battle of Bull Run
- Public demand pushed U.S. General-in-Chief Winfield Scott to advance on the South before adequately training his untried troops. Scott ordered General Irvin McDowell to advance on Confederate troops stationed at Manassas Junction, Virginia. McDowell attacked on July 21, and was initially successful, but the introduction of Confederate reinforcements resulted in a Southern victory and a chaotic retreat toward Washington by federal troops.
- General McDowell Is Replaced
- Suddenly aware of the threat of a protracted war and the army's need for organization and training, Lincoln replaced McDowell with General George B. McClellan.
- A Blockade of the South
- To blockade the coast of the Confederacy effectively, the federal navy had to be improved. By July, the effort at improvement had made a difference and an effective blockade had begun. The South responded by building small, fast ships that could outmaneuver Union vessels.
- Port Royal, South Carolina
- On November 7, 1861, U.S. Captain Samuel F. Dupont's warships silenced Confederate guns in Fort Walker and Fort Beauregard. This victory enabled General Thomas W. Sherman's troops to occupy first Port Royal and then all the famous Sea Islands of South Carolina.
- Abraham Lincoln Takes Action
- On January 27, President Lincoln issued a war order authorizing the Union to launch a unified aggressive action against the Confederacy. General McClellan ignored the order.
- McClellan Loses Command
- On March 8, President Lincoln -- impatient with General McClellan's inactivity -- issued an order reorganizing the Army of Virginia and relieving McClellan of supreme command. McClellan was given command of the Army of the Potomac, and ordered to attack Richmond. This marked the beginning of the Peninsular Campaign.
- Battle of the "Monitor" and the "Merrimac"
- In an attempt to reduce the North's great naval advantage, Confederate engineers converted a scuttled Union frigate, the U.S.S. Merrimac, into an iron-sided vessel rechristened the C.S.S. Virginia. On March 9, in the first naval engagement between ironclad ships, the Monitor fought the Virginia to a draw, but not before the Virginia had sunk two wooden Union warships off Norfolk, Virginia.
- The Battle of Shiloh
- On April 6, Confederate forces attacked Union forces under General Ulysses S. Grant at Shiloh, Tennessee. By the end of the day, the federal troops were almost defeated. Yet, during the night, reinforcements arrived, and by the next morning the Union commanded the field. When Confederate forces retreated, the exhausted federal forces did not follow. Casualties were heavy -- 13,000 out of 63,000 Union soldiers died, and 11,000 of 40,000 Confederate troops were killed.
- Fort Pulaski, Georgia
- U.S. General Quincy A. Gillmore battered Fort Pulaski, the imposing masonry structure near the mouth of the Savannah River, into submission in less than two days, (April 10-11, 1862).
- New Orleans
- U.S. Flag Officer David Farragut led an assault up the Mississippi River. By April 25, he was in command of New Orleans.
- The Peninsular Campaign
- In April, General McClellan's troops left northern Virginia to begin the Peninsular Campaign. By May 4, they occupied Yorktown, Virginia. At Williamsburg, Confederate forces prevented McClellan from meeting the main part of the Confederate army, and McClellan halted his troops, awaiting reinforcements.
- "Stonewall" Jackson Defeats Union Forces
- Confederate General Thomas J. "Stonewall" Jackson, commanding forces in the Shenandoah Valley, attacked Union forces in late March, forcing them to retreat across the Potomac. As a result, Union troops were rushed to protect Washington, D.C.
- The Battle of Seven Pines (Fair Oaks)
- On May 31, the Confederate army attacked federal forces at Seven Pines, almost defeating them; last-minute reinforcements saved the Union from a serious defeat. Confederate commander Joseph E. Johnston was severely wounded, and command of the C.S. Army of Northern Virginia fell to Robert E. Lee.
- The Seven Days' Battles
- Between June 26 and July 2, Union and Confederate forces fought a series of battles: Mechanicsville (June 26-27), Gaines's Mill (June 27), Savage's Station (June 29), Frayser's Farm (June 30), and Malvern Hill (July 1). On July 2, the Confederates withdrew to Richmond, ending the Peninsular Campaign.
- A New Commander of the Union Army
- On July 11, Major-General Henry Halleck was named general-in-chief of the Union army.
- Pope's Campaign
- Union General John Pope suffered defeated at the Second Battle of Bull Run on August 29-30. General Fitz-John Porter was held responsible for the defeat because he had failed to commit his troops to battle quickly enough; he was forced out of the army by 1863.
- Harper's Ferry
- Union General McClellan defeated Confederate General Lee at South Mountain and Crampton's Gap in September, but did not move quickly enough to save Harper's Ferry, which fell to Confederate General Jackson on September 15, along with a great number of men and a large body of supplies.
- On September 17, Confederate forces under General Lee were caught by General McClellan near Sharpsburg, Maryland. This battle proved to be the bloodiest day of the war; 2,108 Union soldiers were killed and 9,549 wounded -- 2,700 Confederates were killed and 9,029 wounded. The battle had no clear winner, but because General Lee withdrew to Virginia, McClellan was considered the victor. The battle convinced the British and French -- who were contemplating official recognition of the Confederacy -- to reserve action, and gave Lincoln the opportunity to announce his Preliminary Emancipation Proclamation (September 22), which would free all enslaved people in areas rebelling against the United States, effective January 1, 1863.
- The Battle of Fredericksburg
- General McClellan's slow movements, combined with General Lee's escape, and continued raiding by Confederate cavalry, dismayed many in the North. On November 7, Lincoln replaced McClellan with Major-General Ambrose E. Burnside. Burnside's forces were defeated in a series of attacks against entrenched Confederate forces at Fredericksburg, Virginia, and Burnside was replaced with General Joseph Hooker.
- Emancipation Proclamation
- In an effort to placate the slavery-legal border states, Lincoln resisted the demands of radical Republicans for complete abolition. Yet some Union generals, such as General B. F. Butler, declared enslaved people escaping to their lines "contraband of war," not to be returned to their masters. Other generals decreed that those enslaved by men rebelling against the Union were to be considered free. Congress, too, had been moving toward abolition. In 1861, Congress had passed an act stating that all enslaved people employed against the Union were to be considered free. In 1862, another act stated that all people enslaved by men who supported the Confederacy were to be considered free. Lincoln, aware of the public's growing support of abolition, issued the Emancipation Proclamation on January 1, 1863, declaring that all enslaved people in areas still in rebellion were, in the eyes of the federal government, free.
- The First Conscription Act
- Because of recruiting difficulties, an act was passed making all men between the ages of 20 and 45 liable to be called for military service. Service could be avoided by paying a fee or finding a substitute. The act was seen as unfair to the poor, and riots in working-class sections of New York City broke out in protest. A similar conscription act in the South provoked a similar reaction.
- The Battle of Chancellorsville
- On April 27, Union General Hooker crossed the Rappahannock River to attack General Lee's forces. Lee split his army, attacking a surprised Union army in three places and almost completely defeating them. Hooker withdrew across the Rappahannock River, giving the South a victory, but it was the Confederates' most costly victory in terms of casualties.
- The Vicksburg Campaign
- Union General Grant won several victories around Vicksburg, Mississippi, the fortified city considered essential to the Union's plans to regain control of the Mississippi River. On May 22, Grant began a siege of the city. After six weeks, Confederate General John Pemberton surrendered, giving up the city and 30,000 men. The capture of Port Hudson, Louisiana, shortly thereafter placed the entire Mississippi River in Union hands. The Confederacy was split in two.
- The Gettysburg Campaign
- Confederate General Lee decided to take the war to the enemy. On June 13, he defeated Union forces at Winchester, Virginia, and continued north to Pennsylvania. General Hooker, who had been planning to attack Richmond, was instead forced to follow Lee. Hooker, never comfortable with his commander, General Halleck, resigned on June 28, and General George Meade replaced him as commander of the Army of the Potomac.
- On July 1, a chance encounter between Union and Confederate forces began the Battle of Gettysburg. In the fighting that followed, Meade had greater numbers and better defensive positions. He won the battle, but failed to follow Lee as he retreated back to Virginia. Militarily, the Battle of Gettysburg was the high-water mark of the Confederacy; it is also significant because it ended Confederate hopes of formal recognition by foreign governments. On November 19, President Lincoln dedicated a portion of the Gettysburg battlefield as a national cemetery, and delivered his memorable "Gettysburg Address."
- The Battle of Chickamauga
- On September 19, Union and Confederate forces met on the Tennessee-Georgia border, near Chickamauga Creek. After the battle, Union forces retreated to Chattanooga, and the Confederacy maintained control of the battlefield.
- The Battle of Chattanooga
- After Union General Rosecrans's debacle at Chickamauga, Confederate General Braxton Bragg's army occupied the mountains that ring the vital railroad center of Chattanooga. Grant, brought in to save the situation, steadily built up offensive strength, and on November 23-25 burst the blockade in a series of brilliantly executed attacks. Union forces pushed Confederate troops away from Chattanooga. The victory set the stage for U.S. General Sherman's Atlanta Campaign.
- The Siege of Knoxville
- The difficult strategic situation of the federal armies after Chickamauga enabled Bragg to detach a force under Longstreet to drive Burnside out of eastern Tennessee. Burnside sought refuge in Knoxville, which he successfully defended from Confederate assaults.
- Grant's Wilderness Campaign
- General Grant, promoted to commander of the Union armies, planned to engage Lee's forces in Virginia until they were destroyed. North and South met and fought in an inconclusive three-day battle in the Wilderness. Lee inflicted more casualties on the Union forces than his own army incurred, but unlike Grant, he had no replacements.
- The Battle of Spotsylvania
- General Grant continued to attack Lee. At Spotsylvania Court House, he fought for five days, vowing to fight all summer if necessary.
- The Battle of Cold Harbor
- Grant again attacked Confederate forces at Cold Harbor, losing over 7,000 men in twenty minutes. Although Lee suffered fewer casualties, his army never recovered from Grant's continual attacks. This was Lee's last clear victory of the war.
- The Siege of Petersburg
- Grant hoped to take Petersburg, below Richmond, and then approach the Confederate capital from the south. The attempt failed, resulting in a ten month siege and the loss of thousands of lives on both sides.
- Confederate Troops Approach Washington, D.C.
- Confederate General Jubal Early led his forces into Maryland to relieve the pressure on Lee's army. Early got within five miles of Washington, D.C., but on July 13, he was driven back to Virginia.