Irvin McDowell lost it, although he was not a bad general.
General Pope lost to General Lee at Second Bull Run.
The First Battle of Manassas as it was known in the South, or First Battle of Bull Run in the North.
For the First Bull Run, the Union commander was Major General Irvin McDowell. For the Second Bull Run, Major General John Pope led the Union armies.
At the First Battle of Bull Run, Southern forces were led by generals Beauregard and Johnston. At the Second Battle of Bull Run, the commanding officer of all Southern forces was General Robert E. Lee.
Irvin McDowell
Confederate General PT Beauregard commanded the Army of the Potomac and General Joseph Johnston commanded the Army of the Shenandoah at the first Battle of Bull Run.
General Irvin McDowell
Joseph E. Johnston. He deferred some power to P.G.T. Beauregard, on account of his better familiarity with the terrain.
General Thomas Jonathan Jackson earned the name "Stonewall Jackson at the first Battle of Bull Run.
General McDowell was the first commanding officer of the Union's Army of the Potomac. Under him the Army lost it's first major battle, the battle of Manassas or Bull Run. He was quickly replaced with General George B. McClellan.
The Union Army under General Irving McDowell was the attacking army at the First Battle of Bull Run also known as Manassas.
The unfortunate General who was commanding the Army of the Potomac in the first months of the war, when the press and politicians were calling for some action. McDowell knew his army was not ready for combat, but he was pushed into it, and lost the First Battle of Bull Run.