By Gary Gallagher Ph.D., University of Virginia
The First Manassas or Bull Run was the first massive battle of the Civil War. Against expectations, it ended with the South’s victory. There was more than one reason for the Union’s defeat.

The first battle of the Civil War was an almost hastily-made decision, despite all the military gurus behind the scenes. Abraham Lincoln, who had recently become the president, wanted to satisfy the nation’s desire for a quick and decisive attack against the rebels. He believed that the army Generals were too skeptical.
Winfield Scott was one of the most influential figures of war in 1861, and one of the most intelligent generals ever. His ‘Anaconda Plan,’ which was a sound military strategy, was rejected because it took too long to implement. Scott was not the only one who tried to convince Lincoln that it takes long to win the war. Irvin McDowell, a commander of the First Manassas, who commanded the largest United States force in the field, thought the same. Neither of them, however, could convince the other decision-makers to wait longer.
This is a transcript from the video series The American Civil War. Watch it now, on Wondrium.
When Scott and McDowell failed to buy the time they needed to prepare the army, McDowell’s men were sent to the first sizable military campaign of the war – First Manassas or Bull Run.
Learn more about the Confederacy and its generals.
Naming the First Manassas or Bull Run
Battles of the Civil War usually had two names: one from the Northern point of view, and one from the Southern. The North tended to name the battles after a terrain feature in the area, while the South typically used the name of a railroad crossroads or a town.
The Confederates named this battle after the railroad junction – Manassas Junction. The Federals named it after the local bay – Bull Run.
There are many other examples of this dual-naming in Civil War, just to point out a few: Antietam, the Union name for the battle in Western Maryland, named after the creek. Sharpsburg is the Confederate name for the same battle, named after the little local village. The Battle of Murfreesboro – Confederate name – or Stone’s River – the Union name – in Tennessee is another example.
The Northern Troops and Commanders of the First Manassas

First Manassas or Bull Run put four forces against one another in Virginia: two Confederate and two Union. McDowell had his army of 35,000 men, a few miles away from Washington.
This was the most significant American army up to that point of history, and it was commanded by a former staff officer with no field experience. McDowell had taught tactics at West Point, and his friendship with the Secretary of the Treasury – Salmon P. Chase – helped him get his place in war.
McDowell was known for his gluttony. A famous anecdote about him is the story of how he ate one whole watermelon with the seeds and the rind in front of his staffers. He was not a leader who would achieve a great victory.
Robert Patterson was a veteran of the War of 1812, who commanded the other Union force with 18,000 men. They were in the lower Shenandoah Valley.
The Southern Troops and Commanders of the First Manassas
Gustave Toutant Beauregard was twenty miles away from McDowell, with the main Southern force of 20,000 men, near Manassas Junction. Beauregard was also a former staff officer, but his tenure had lasted less than one week. Clearly, the Northerners were not the only ones who had their largest army commanded by a person with no field experience.
Beauregard was a Louisiana Creole and a very vain man who even dyed his hair – an unusual thing for men at the time. When the Northern blockade took place, he could not get the dye anymore; therefore, his hair at that point of the war looked nothing like the beautiful dark hair of the first pictures, but gray. He had a kind of Napoleonic complex. Even though he was not a brilliant general, on the whole, his competency cannot be ignored.

The other Confederate force of 12,000 men was commanded by Joseph Eggleston Johnston, in the lower valley. Johnston was from Virginia, and his name is repeated very often in the course of the Civil War. He had spent a distinguished career in the prewar army, had fought bravely in Mexico, and had been wounded there, but his reputation might be exaggerated.
Beauregard and Johnston had a significant military advantage over the Northerners: the Manassas Gap Railroad connecting their two troops. Thus, they could reinforce each other more quickly than the Federals.
Learn more about the advantages of each side of the Civil War.
How the First Massive Battle of the American Civil War Began
In addition to having untrained soldiers, the commanders of both sides turned out to have the same strategy. They both wanted to avoid a direct attack, march on the other army, focus in front, and turn the opponents leftwards. Patterson’s mission was to hold Johnston in the Shenandoah Valley and let McDowell deal with Beauregard.
McDowell left Washington on July 16 with his army and moved slowly to the west. Patterson failed to hold Johnston in the valley, and Johnston commanded his men to move to Manassas by railway, to join Beauregard. Some smaller units in Virginia began their march toward Beauregard as well.
Learn more about the controversies and clashes that set the stage for war.
The Confederates utilized their interior lines by July 20, to bring together a formidable force near Manassas Junction. McDowell was still slowly moving forward to reach Manassas Junction. This 20 and something miles takes several days for 35,000 men to cover.
On July 21, 1861, McDowell reached the position where he could implement his plan and try to turn the southern army left. This was how the battle eventually began.
Common Questions About the Commanders of the First Manassas or Bull Run
McDowell was a Federal commander of the First Manassas or Bull Run. The troops under his command were defeated in the first battle of the Civil War.
Winfield Scott was known as the Grand Old Man of the Army for his many years of service. He established a very strategic plan for the Union army to win the Civil War, even though he was not a commander of the First Manassas or Bull Run on the battlefield.
Beauregard was the Confederacy’s first brigadier general. He was a commander of the First Manassas or Bull Run and led the Union army to retreat and their defeat in the first battle of the Civil War.
As a commander of the First Manassas or Bull Run on the Confederacy side, Johnston shared the honor of the first victory of the war with his army.