How did the Battle of Bull Run change Americans expectations of the civil war?

The First Battle of Bull Run, also known as the Battle of Manassas, marked the first major land battle of the American Civil War. On July 21, 1861, Union and Confederate armies clashed near Manassas Junction, Virginia. The engagement began when about 35,000 Union troops marched from the federal capital in Washington, D.C. to strike a Confederate force of 20,000 along a small river known as Bull Run. After fighting on the defensive for most of the day, the rebels rallied and were able to break the Union right flank, sending the Federals into a chaotic retreat towards Washington. 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.

Prelude to the First Battle of Bull Run (Manassas)

By July 1861, two months after Confederate troops opened fire on Fort Sumter to begin the Civil War, the northern press and public were eager for the Union Army to make an advance on Richmond ahead of the planned meeting of the Confederate Congress there on July 20. Encouraged by early victories by Union troops in western Virginia and by the war fever spreading through the North, President Abraham Lincoln ordered Brigadier General Irvin McDowell to mount an offensive that would hit quickly and decisively at the enemy and open the way to Richmond, thus bringing the war to a mercifully quick end. The offensive would begin with an attack on more than 20,000 Confederate troops under the command of General P.G.T. Beauregard camped near Manassas Junction, Virginia (25 miles from Washington, D.C.) along a little river known as Bull Run.

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