Santa clasue
Technically, yes. For example, in spring 1862, there was no General-in-Chief of the Union armies. Lincoln was effectively in that job himself. But he didn't want to be (unlike the opposing President), and he handed over the task to a qualified West-Pointer as soon as he could.
Robert E. Lee, he couldn't fight against his place of birth, Virginia
Robert E. Lee was offered command of the Union Armies by President Lincoln. He turned it down because he felt he was a Virginian first and could not fight against is State.
Abraham Lincoln
The northern territories of the union armies fought with the southern territories. After John Brown's massacre, the union armies marched to Virginia to meet with Robert Lee's southern armies.
If you mean The Union in the US Civil War, President Abraham Lincoln lead the Union. If you mean who led A Union, President Ronald Regan was, at one time a union president.
No. Lincoln was the Union leader. Jefferson Davis was the Confederate leader.
George Brinton McClellan.
Abraham Lincoln died, the Union had another victory, and the slaves were freed.
You probably mean Lee. He was asked to lead the Union armies, but decided to stay with his home state of Virginia.
Ulysses S. Grant
The President was Abraham Lincoln, the general was Ulysses S. Grant. Lincoln was assassinated after the civil war.