Based on the question of who was the commander of the US during the US Civil War, the Commander in Chief was US President Abraham Lincoln. In terms of overall command of the Union's military establishment, Lincoln whose Secretary of War, Edwin Stanton, over saw the conduct of the war. On a day to day basis, however, the generals appointed by Lincoln and -or Stanton carried out the overall civilian plan to end the Southern rebellion for their independence.
Ulysses s grant
U. S. Grant.
General Robert E Lee,
The commander of the Confederacy was General Robert E. Lee, the commander of the Union was General Ulysses Simpson Grant (later he became the 18th President of the USA).
McClelland then Grant. Robert E. Lee was Lincoln's fist choice to lead the union army at the beginning of the war but, Lee said "I cannot fight against my own birthplace." So they chose Winfield Scott as commander.
Someone who is now dead
For the US Civil War; most likely the commander in chief; Lincoln.
Lincoln was never a general, although as POTUS during the Civil War, he was Commander-In-Chief of all US forces.
The US capitol now and during the US Civil War was Washington DC.
Politically, the C.S.A. was controlled by President Jefferson Davis who was also Commander in Chief.Robert E. Lee
Abraham Lincoln was President during the US Civil War.
Us civil war