(A) ** North (Union)
(B) South (Confederate states)
EXPLANATIONS BELOW
Concept note-1: -The Confederate victory gave the South a surge of confidence and shocked many in the North, who realized the war would not be won as easily as they had hoped.
Concept note-2: -Both armies were sobered by the fierce fighting and the many casualties and realized that the war was going to be much longer and bloodier than either had anticipated.
Concept note-3: -On July 21, 1861, in the first major land battle of the Civil War, a large Union force under General Irvin McDowell is routed by a Confederate army under General Pierre G.T. Beauregard.
Concept note-4: -Federal forces under General Irvin McDowell attempted to flank Confederate positions by crossing Bull Run but were turned back. The end result of the battle was a Confederate victory and Federal forces retreated to the defenses of Washington, DC.