I fear that the asker of this particular question has received their information from an unreliable source. Since Robert E. Lee commanded the battle as second Manassas/Bull Run the asker can only be refering to 1st Manassas/Bull Run so I shall answer that.
While Lee would later make his name as one of the finest American General to ever live before 1st Manassas/Bull Run he was unavailable to Command a Confederate Army in the field because he was not recognized as a Confederate General.
In early 1861 Lee was Commander of the Virginia Militia and acted as a liasion officer to the Confederacy during the period of time that 1st Manassas/Bull Run occured. During that period the Virginian forces had yet to be turned over to the Confederacy.
Even if he had been available he would not have been offered the job as Beauregard had earned the position at that time by being the first and only successful General the South had while Joe Johnston got command in the Shenandoah Valley on the merit of being the Confederacy only other General.
Robert E. Lee refused to command the Confederate troops at the first battle of Bull Run (also known as the Battle of Manassas) because he believed that he would not be able to effectively lead the army due to his lack of knowledge of the current situation and terrain. Instead, he served as an advisor to Confederate President Jefferson Davis.
battle of shiloh
Under the command of Union General James Harrison Wilson, his army of 9,000 troops were successful in defeating the forces of Confederate General Nathan Forest. Forest had a defending army of 4,000 troops. Confederate forces took on heavy casualties in the battle.
70,000 troops of the North Virginia army under General Robert E. Lee's command.
The Union's military high command was aware that Confederate troops were forming a large concentration for what would be the Battle of Chickamauga. They attempted a counter concentration that called for Union troops in Georgia and as faraway as Minnesota. None of these troops were able to reach Chickamauga until after the battle was over.
At the First Battle of Manassas Gen. Joseph Eggleston Johnston had the overall command of the Confederate Army, while Gen. Pierre Gustave Toutant Beauregard was left the tactical direction of the battle. At the Second Battle of Manassas the Confederate leader was Gen. Robert E. Lee.
battle of shiloh
Under the command of Union General James Harrison Wilson, his army of 9,000 troops were successful in defeating the forces of Confederate General Nathan Forest. Forest had a defending army of 4,000 troops. Confederate forces took on heavy casualties in the battle.
Confederate generals always had troops and slaves under their command.
71,699
70,000 troops of the North Virginia army under General Robert E. Lee's command.
The Union's military high command was aware that Confederate troops were forming a large concentration for what would be the Battle of Chickamauga. They attempted a counter concentration that called for Union troops in Georgia and as faraway as Minnesota. None of these troops were able to reach Chickamauga until after the battle was over.
At the First Battle of Manassas Gen. Joseph Eggleston Johnston had the overall command of the Confederate Army, while Gen. Pierre Gustave Toutant Beauregard was left the tactical direction of the battle. At the Second Battle of Manassas the Confederate leader was Gen. Robert E. Lee.
The Union troops were able to defeat the Confederate troops that had invaded the North
Fremont
Lots of Confederate and Union troops alike
The Union troops crossed the Mississippi River and drove the Confederate troops out of Vicksburg
The Union troops crossed the Mississippi River and drove the Confederate troops out of Vicksburg