Answer:
Slavery
Explanation:
States' rights regarding slavery was one of the main issues dividing the North and South that led to the Civil War.
The correct answer is Confederate reinforcements won the battle and forced the Union troops to retreat.
It was the first major battle of the American Civil War.
Just months after the war began at the Battle of Fort Sumter, a public outcry was made in the Union for a march against the Confederate capital Richmond, Virginia, which could bring the war to an end quickly. Giving in to this political pressure, inexperienced Union Army troops under the command of Brigadier General Irvin McDowell advanced through Bull Run (Occoquan River) against the equally immature Confederate Army under the command of Brigadier General P.G.T. Beauregard near Manassas Junction.
