Eastern Theater of the American Civil War in the context of "Chattanooga campaign"

The American state of Virginia became a prominent part of the Confederacy when it joined during the American Civil War. As a Southern slave-holding state, Virginia held the state convention to deal with the secession crisis and voted against secession on April 4, 1861. Opinion shifted after the Battle of Fort Sumter on April 12, and April 15, when U.S. President Abraham Lincoln called for troops from all states still in the Union to put down the rebellion. For all practical purposes, Virginia joined the Confederacy on April 17, though secession was not officially ratified until May 23. A Unionist government was established in Wheeling and the new state of West Virginia was created by an act of Congress from 50 counties of western Virginia, making it the only state to lose territory as a consequence of the war. Unionism was indeed strong also in other parts of the State, and during the war the Restored Government of Virginia was created as rival to the Confederate Government of Virginia, making it one of the states to have 2 governments during the Civil War.

In May, it was decided to move the Confederate capital from Montgomery, Alabama, to Richmond, Virginia, in large part because, regardless of the Virginian capital's political status, its defense was deemed vital to the Confederacy's survival. On May 24, 1861, the U.S. Army moved into northern Virginia and captured Alexandria without a fight. Most of the battles in the Eastern Theater of the American Civil War took place in Virginia because the Confederacy had to defend its national capital at Richmond, and public opinion in the North demanded that the Union move "On to Richmond!" The successes of Robert E. Lee in defending Richmond are a central theme of the military history of the war. The White House of the Confederacy, located a few blocks north of the State Capitol, became home to the family of Confederate leader, former Mississippi Senator Jefferson Davis.

The Battle of Brandy Station, also called the Battle of Fleetwood Hill, was the largest predominantly cavalry engagement of the American Civil War, as well as the largest ever to take place on American soil. It was fought on June 9, 1863, around Brandy Station, Virginia, at the beginning of the Gettysburg campaign by the Union cavalry under Maj. Gen. Alfred Pleasonton against Maj. Gen. J. E. B. Stuart's Confederate cavalry.

Union commander Pleasonton launched a surprise dawn attack on Stuart's cavalry at Brandy Station. After an all-day fight in which fortunes changed repeatedly, the Federals retired without discovering Gen. Robert E. Lee's infantry camped near Culpeper. This battle marked the end of the Confederate cavalry's dominance in the East. From this point in the war, the Federal cavalry gained strength and confidence.

The Army of the Potomac was the primary field army of the Union army in the Eastern Theater of the American Civil War. It was created in July 1861 shortly after the First Battle of Bull Run and was disbanded in June 1865 following the surrender of the Confederate Army of Northern Virginia in April.

George Brinton McClellan (December 3, 1826 – October 29, 1885) was an American military officer, politician, and engineer who served as the 24th governor of New Jersey from 1878 to 1881 and as Commanding General of the United States Army from November 1861 to March 1862. He was also chief engineer and vice president of the Illinois Central Railroad, and later president of the Ohio and Mississippi Railroad in 1860.

A West Point graduate, McClellan served with distinction during the Mexican–American War. He was a railway executive and engineer until the outbreak of the American Civil War in 1861. Early in the conflict, McClellan was appointed to the rank of major general and played an important role in raising the Army of the Potomac, which served in the Eastern Theater.

Henry Wager Halleck (January 16, 1815 – January 9, 1872) was a senior United States Army officer, scholar, and lawyer. A noted expert in military studies, he was known by a nickname that became derogatory: "Old Brains". He was an important participant in the admission of California as a state and became a successful lawyer and land developer. Halleck served as the General-in-Chief of the Armies of the United States from 1862 to 1864, and then became Chief of Staff for the remainder of the war when Ulysses S. Grant was appointed to that position.

Early in the American Civil War, Halleck was a senior Union Army commander in the Western Theater. He commanded operations in the West from 1861 until 1862, during which time, while the Union armies in the East were repeatedly defeated and held back, the troops under Halleck's command won many important victories. However, Halleck was not present at those battles, and his subordinates earned most of the recognition. The only operation in which Halleck exercised field command was the so-called siege of Corinth in the spring of 1862, a Union victory which he conducted with unnecessary caution, which allowed the Confederate force to escape. Halleck also developed rivalries with several of his subordinate generals, such as Grant and Don Carlos Buell. In July 1862, following Major General George B. McClellan's failed Peninsula Campaign in the Eastern Theater, Halleck was promoted to general-in-chief. Halleck served in this capacity for about a year and a half.

Philip Henry Sheridan (March 6, 1831 – August 5, 1888) was a career United States Army officer and a Union general in the American Civil War. His career was noted for his rapid rise to major general and his close association with General-in-chief Ulysses S. Grant, who transferred Sheridan from command of an infantry division in the Western Theater to lead the Cavalry Corps of the Army of the Potomac in the East. In 1864, he defeated Confederate forces under General Jubal Early in the Shenandoah Valley and his destruction of the economic infrastructure of the Valley, called "The Burning" by residents, was one of the first uses of scorched-earth tactics in the war. In 1865, his cavalry pursued Gen. Robert E. Lee and was instrumental in forcing his surrender at Appomattox Courthouse.

In his later years, Sheridan fought in the Indian Wars against Native American tribes of the Great Plains. He was instrumental in the development and protection of Yellowstone National Park, both as a soldier and a private citizen. In 1883, Sheridan was appointed general-in-chief of the U.S. Army, and in 1888 he was promoted to the rank of General of the Army during the term of President Grover Cleveland.

The Texas Brigade (also known as Hood's Brigade) was an infantry formation of the Confederate Army that distinguished itself in the American Civil War. Along with the Stonewall Brigade, they were considered the Army of Northern Virginia's shock troops. It fought in every major battle of the Eastern Theater except Chancellorsville.

Ulric Dahlgren (April 3, 1842 – March 2, 1864) was an American military officer who served as colonel in the Union Army during the American Civil War. He was the son of Union Navy Rear Admiral John A. Dahlgren and nephew to Confederate Brigadier General Charles G. Dahlgren.

He fought in several key battles in the Eastern Theater of the American Civil War and had his leg amputated below the knee after being wounded at the Battle of Gettysburg. He returned to military service and was killed in 1864 during the Battle of Walkerton while leading a raid on the Confederate capital of Richmond, Virginia.