Why were the confederate and union capitals' so close to each other during the civil war?

Answer The US capitol was in Washington, D.C. The capitol of the Confederacy was originally in Montgomery, AL. However, Virginia was debating if they would secede and join the Confederacy. Somehow, the offer was made to move the Confederate capitol to Richmond in order to entice the State to join. Virginia seceded from the Union. General Robert E. Lee followed the decision of his State. The Capitol was moved to Richmond.