On May 31, 1861, Major General Robert E. Lee, commander of all Confederate forces in Virginia, met with President Jefferson Davis and the recently arrived Brigadier General Pierre Gustave Toutant Beauregard to update them on the emerging crisis in Northern Virginia. Union troops had crossed the Potomac River and occupied Alexandria and were now moving into Fairfax County. Lee felt that their ultimate objective was Manassas Junction on the Orange and Alexandria Railroad 28 miles southwest of Washington. Richmond was only 100 miles south of Washington and there were two likely paths of invasion to the Confederate capitol. One was along the Orange and Alexandria Railroad and the other was up the Shenandoah Valley. The Confederates feared a simultaneous invasion along both routes and given their manpower shortage needed to be able to shuttle troops between these two locations. The Manassas Gap Railroad connected Manassas Junction to the Shenandoah Valley and was the lifeline that connected the two regions. Beauregard arrived at Manassas Junction the next day, assumed command, and quickly began organizing its defense. Beauregard was a West Point graduate who served in the Mexican War. Prior to taking command at Fort Sumter, he had never commanded more than a company of soldiers. After Fort Sumter he was the most well-known general in the south. He quickly got to work and built 12 forts around the junction and amassed about 22,000 men there.

In the Shenandoah Valley, sixty-five miles away, Brigadier General Joseph Johnston commanded about 11,000 troops near Winchester. Johnston was also a West Point graduate who had served in the Mexican War with over 35 years of military experience. He had been wounded five times in combat over that time and had been breveted for gallantry on three occasions. His command was composed of 5 brigades and was called the Army of the Shenandoah.

The man who would be commanding the Union forces was Brigadier General Irvin McDowell from Ohio. A West Point graduate, McDowell had previously commanded only a handful of men and was before the war working in the office of the Adjutant General. McDowell had friends in high places, most notably Secretary of the Treasury Salmon P. Chase also from Ohio, who advocated for his appointment as a Brigadier General. After the fall of Fort Sumter, President Lincoln called for 75,000 volunteers for an enlistment period of three months. McDowell didn’t have much time to try and mold these citizen soldiers into an army. Political and public pressure on him was enormous to attack during this period. In late June McDowell submitted his plan to march on Manassas Junction and then to Richmond.

In order for McDowell to preserve his numerical advantage over Beauregard it was essential that Johnston’s army in the Shenandoah not be allowed to move from the Shenandoah Valley to Manassas Junction via the Manassas Gap Railroad. It would be the job of Brigadier General Robert Patterson and his 18,000 troops to keep Johnston in the valley. Patterson was a 69-year-old veteran of the War of 1812. His force was in the Martinsburg, WV, area.

Finally on July 16th McDowell set out for Manassas Junction with his army (known then as the Army of Northeastern Virginia), which was divided into five divisions. Brigadier General Daniel Tyler commanded the first division, Colonel David Hunter led the second, Colonel Samuel P. Heintzelman the third, Brigadier General Theodore Runyon the fourth and Colonel Dixon Miles the fifth. They covered 10 miles on the first day. Straggling was a major problem as the soldiers often fell out of line to pick blackberries and fill their canteens. On the 17th they covered only an additional 5 miles. The slow Union advance gave Beauregard additional time to prepare. The Confederates were behind Bull Run Creek. Its banks were steep, and it was only fordable at certain locations. They were spread out along a seven-mile front with their right flank on the Orange and Alexandria Railroad and their left flank at the Stone Bridge where the Warrenton Turnpike crossed Bull run shown in the map below.

Beauregard had placed five of his brigades in the center near Mitchell’s Ford. He telegraphed Richmond urgently requesting reinforcements. Adjutant General Samuel Cooper telegraphed Johnston near Winchester to get to Manassas as soon as possible. McDowell had originally planned to try and turn the Confederate right but on inspecting the lines on July 18 he concluded that it was not possible given that the roads were very small and the distance his troops would need to cover was too long. Before McDowell left to inspect the lines that morning, he ordered General Tyler to move forward and occupy Centreville and to observe the roads to Bull Road and Warrenton without bringing on a general engagement. At Blackburn’s Ford, Tyler did what he was requested not to do and got involved in a heavy action with Rebel forces under the command of Brigadier General James Longstreet. Tyler was repulsed and retreated in disarray taking about 150 casualties in the process. During the action Beauregard was headquartered nearby at “Yorkshire” Wilmer McLean’s house. Shown below are pictures of Blackburn’s Ford and it’s markers, and markers for Yorkshire.

“Yorkshire” markers- the Wilmer McLean House

McDowell was angry with Tyler but his lapse in judgement did lead to some valuable information for the Federals. McDowell now knew that his attack would have to be directed at the Confederate left rather than the center or the right. While this was occurring, Johnston was giving Patterson the slip in the Shenandoah Valley. Colonel Jeb Stuart’s 1st VA Cavalry was screening Johnston as he began pulling out of the Valley around mid-day on the 18th. He crossed the Blue Ridge Mountains at Ashby’s Gap and boarded a train at Piedmont Station (modern day Delaplane shown in the pictures below) for Manassas Junction. The cavalry and artillery would have to travel overland. There was only one locomotive available and the 35-mile trip would take a total of 4 hours in each direction. This represented the first tactical use of a railroad to deliver troops to the battlefield in American history. Over the next 48 hours about 80% of Johnston’s 11,000 men would make the trip. McDowell had no idea these reinforcements from the Valley were rushing to the battlefield given that he had received assurances from Washington that Patterson had Johnston contained in the Valley. In reality Patterson had actually retreated away from Johnston.

Johnston’s army arrived over July 19-20 while McDowell searched for an upstream ford to use to try and get around the Confederate left flank. Beauregard expected Johnston’s force to march overland and was surprised when Brigadier General Thomas J. Jackson’s troops arrived at Manassas Station by rail. He sent Jackson north to Mitchell’s Ford.

Mitchell’s Ford seen from the Old Centreville Bridge- 38.797213, -77.4577405

Johnston arrived in person at noon on the 20th. McDowell planned to cross Bull Run well beyond the Rebel left flank on the morning of the 21st. Hunter and Heintzelman would cross at Sudley Ford and Poplar Ford, respectively. This flanking force would have about 13,000 troops. Meanwhile Tyler would act as a diversionary force marching down the Warrenton Turnpike to the Stone Bridge. Beauregard completed his plan during the night to throw his force across Bull Run and turn the Union left. If both plans were actually caried out the armies would then just change positions on opposite sides of Bull Run with the Union winding up on the west bank and the Rebels on the east bank. In reality this did not happen because the Union attack would occur first. McDowell’s column was to start out at 2:30 AM but immediately ran into problems. Tyler’s division had been ordered to march first despite the fact that they had the shortest and easiest route. This blocked the march of Hunter and Heintzelman who had the longest route. A further delay occurred when Federal engineers determined that the bridge over Cub Run was not structurally sufficient to support the weight of artillery and needed to be reinforced. The guide of Hunter and Heintzelman’s divisions took a longer route than expected and both divisions would now have to cross at Sudley’s Ford. Guarding the Confederate left flank was a small brigade commanded by Colonel Nathaniel “Shanks” Evans. His 1,100 soldiers were camped on the Van Pelt farm near the Stone Bridge. Tyler’s two lead brigades under Brigadier General Robert C. Schenck and Colonel William T. Sherman came into contact with Evans skirmishers but Evans quickly realized that this was only a diversion.

Evans headquarters at the Van Pelt farm had set up a signal station. Around 8:30 AM at another signal station located on Willcoxen Hill (Signal Hill) eight miles to the southeast Captain E. Porter Alexander noticed the reflection of sunlight off cannons and bayonets on the east side of Bull Run well to the left of Evans position. He sent a message to Evans “Look out for your left. You are turned.”

Leaving four companies of his 4th SC behind to guard Stone Bridge Shanks shifted the remainder of his brigade to the northwest to counter the impending threat. They deployed briefly at “Pittsylvania” the estate of the Carter family to block the approach from Poplar Ford.

Evans received reports that the Union had crossed Bull Run at Sudley Ford and could now outflank him via Sudley Road (see map below).

Evans would need to move again to the open fields across Sudley Road at the base of Matthews Hill facing north. The Battle of First Manassas was about to begin.

Next- Part 2- The Union on the Verge of Victory

Source

The Battle of First Manassas by Henry P. Elliott. Blue and Gray Magazine Volume XXVII, #5, 2011.