From his camps around Warrenton, Virginia, Burnside planned to abandon the army’s movement southwest in favor of a quick dash southeast toward the lower Rappahannock River. There, he would cross quickly and position himself between Lee and the direct route to Richmond. The plan had great promise, but, to accomplish it successfully, speed was essential.With nearly 200,000 combatants—the greatest number of any Civil War engagement—Fredericksburg was one of the largest and deadliest battles of the Civil War. It featured the first opposed river crossing in American military history as well as the Civil War’s first instance of urban combat. 

Hooker's energetic make-over polished the Union army into tip-top condition, and he declared them “the finest army on the planet.” With complete confidence, Hooker orchestrated a “perfect” plan to confront Lee and drive him from his camp at Fredericksburg. Though outmanned, Lee did not retreat. He met Hooker’s challenge head on, engaging him in one of the bloodiest battles of the Civil War. Brilliant tactics by Lee and “Stonewall” Jackson thwarted Hooker’s ambitions and resulted in a victory for the South. Buoyed by the outcome, Lee later launched an offensive into Pennsylvania, where the opposing armies met on the battlefield in Gettysburg in July 1863. Despite the heavy casualties sustained there, the Battle of Chancellorsville is considered Gen. Robert E. Lee’s greatest military victory.  It was the last battle for Confederate Lt. Gen. Thomas J. “Stonewall” Jackson, who was mortally wounded by friendly fire.

How it ended

Union victory. The South’s defeat at Shiloh ended the Confederacy’s hopes of blocking the Union advance into Mississippi and doomed the Confederate military initiative in the West. With the loss of their commander, Gen. Albert Sidney Johnston, in battle, Confederate morale plummeted.

How it ended

Confederate victory. At the end of a summer that had seen disastrous Confederate losses at Gettysburg and Vicksburg, the triumph of the Army of Tennessee at Chickamauga was a well-timed turn-around for the Confederates, but it came at a great cost.  Chickamauga was the second bloodiest battle of the Civil War, ranking only behind Gettysburg, and was by far the deadliest battle in the Western Theater.

The Union made many attempts to invade Richmond. In the Peninsula Campaign of 1862, General George McClellan moved up the James River, almost to the suburbs of the city, but was beaten back by Robert E. Lee in the Seven Days Battles. In 1864–65, General Ulysses S. Grant laid siege to nearby Petersburg. By April 1865, the Confederate government realized the siege was almost over and abandoned the city lest they be captured. The retreating Confederates chose to burn military supplies rather than let them fall into Union hands; the resulting fire destroyed much of central Richmond.

The shock of the Union defeat at the First Battle of Bull Run in July 1861, with demoralized troops wandering the streets of the capital, caused President Abraham Lincoln to order extensive fortifications and a large garrison. That required an influx of troops, military suppliers and building contractors, which would set up a new demand for accommodation, including military hospitals. The abolition of slavery in Washington in 1862 also attracted many freedmen to the city. Except for one attempted invasion by Confederate cavalry leader Jubal Early in 1864, the capital remained impregnable.^[1]

The Chesapeake Bay was an important area of ​​naval action during the Civil War, especially as the Union attempted to blockade Confederate ports. The bay's most famous event was the Battle of Hampton Roads, the first engagement of armored warships in March 1862. The battle marked the end of the era of wooden warships and was a turning point in naval warfare.