150 years ago today, elements of the Army of the Potomac entered Loudoun County. The army had passed this way before. The previous fall the army advanced through Loudoun following Army of Northern Virginia, falling back from the killing fields of Antietam. And just thirty-two weeks later the Federal army was back pursuing the same Confederate army. Except this time everyone was heading north.
Earlier on June 16, 1863, Brigadier-General Gouverneur Warren, chief engineer, advised that, “Leesburg is a very important place, as the lowest fords of the Potomac are in this vicinity.” Warren’s suggestion carried weight. When Army headquarters posted the march orders late that evening, Leesburg featured prominently as a destination:
The Twelfth Corps, General Slocum, will march at 3 a.m. to-morrow for Leesburg, via Hunter’s Mills, crossing the railroad, Dranesville, and the Leesburg turnpike.
The First Corps, General Reynolds, and Eleventh Corps, General Howard, will march at 3 a.m. for Leesburg from Centreville, one corps taking the route by Frying Pan, old Ox road, and Farmwell Station, crossing the railroad: the others by Gum Springs, Farmwell, crossing Goose Creek, near Trappe Rock.
The Fifth Corps, General Meade, will march from Manassas at 3 a.m. for Leesburg, via Centreville and Gum Springs. The corps marching from Centreville by Gum Springs will keep to the right of the road in the fields near Gum Springs, to enable the Fifth Corps to pass on by the old Carolina road to Leesburg.
The before-mentioned corps will encamp on Goose Creek to-morrow night.
Headquarters at Farmwell Station to-morrow night. Corps en route will report their march and place of camp to morrow night at 7 p.m. at that point and for orders.
The corps will keep up communication with each other from time to time, if necessary.
The routes and places are by the McDowell map of January 1, 1862. In this, as in all future marches, the corps will, in case of attack, march to the sound of heaviest firing.
The Third, Sixth, and Second Corps will follow to-morrow p.m., the Second Corps following the Twelfth; the Fifth Corps following by Germantown and Frying Pan; the Third Corps following by Gum Springs. Each corps commander will guard and care for his trains.
The Reserve Artillery will follow with the Twelfth Corps, General Slocum.
It is suggested to corps commanders that easier marches for the commands will be made by lying by in the middle of the day, and marching early in the morning and late at night.
The orders used place-names defined on the “McDowell Map.” That being the army’s point of reference, I’ll use it too. The map below shows the intertwining lines of march for the First, Fifth, Eleventh, and Twelfth Corps. The remaining corps and artillery reserve were to follow those four leading formations.
Had those orders stood, four corps – First, Fifth, Eleventh, and Twelfth – and the reserve artillery would converge on Leesburg. But Major-General Joseph Hooker’s appreciation for the situation changed overnight. Sensing reports of Confederate movements in Maryland were exaggerated (“rumor” was the word out of his headquarters), Hooker ordered his cavalry to start probing towards Aldie.
And army headquarters adjusted the march orders. Second Corps was to, “encamp in the vicinity of Sangster’s Station to-night. Sixth Corps at Fairfax Station, Twelfth Corps at Dranesville, Eleventh Corps at Guilford Station. First Corps at Goose Creek, Fifth Corps at Gum Springs, Third Corps at Centreville; headquarters near Fairfax Station.” However, as Major-General John Reynolds pointed out, army headquarters had confused the routes of First and Eleventh Corps. Coordinating with Major-General O. O. Howard, he switched the designated stops for the respective corps. With the changes to the march, the infantry and cavalry forces took up these general positions in Loudoun and adjacent Fairfax County (the county boundary, in case you don’t recognize it, is the dashed line running from upper right starting at the Potomac above Drainesville):
Not depicted on the map is the cavalry division of Major-General Julius Stahel. My excuse is that division was not with the Army of the Potomac at the time in question, but rather part of the Washington Defenses. Furthermore, I’d have to break out symbols for regiments as Stahel’s troopers were scattered all about. However, one of those detachments performed a valuable duty on June 17 by patrolling into Leesburg, verifying no Confederate force was there.
By late evening, Major-General Daniel Butterfield, Army Chief of Staff, summarized the situation in an update to Major-General Alfred Pleasonton, commanding the Cavalry Corps:
General Howard is at Goose Greek (Trappe Rock mill-dam and canal lock). ….
The advance of the infantry is suspended until further information of the enemy’s movements. Two regiments of Stahel move early to-morrow morning to Warrenton, Sulphur Springs, Rappahannock Station, &c. ….
If Lee’s army is in rear of his cavalry, we shall move up by forced marches with the infantry. Give us any indications of it as soon as possible.
In other words, the Army of the Potomac had to pause. Sure, we know well that one corps of the Army of Northern Virginia was already crossing the Potomac, and two more were marching fast for Maryland. But Hooker didn’t know that… or at least didn’t know it as fact. Put yourself in his shoes for a moment, and think about his primary responsibility – Washington.
For June 17, the itinerary of the Army of the Potomac stated:
The First Corps marched from Manassas Junction to Herndon Station; the Second Corps from Wolf Run Shoals to Sangster’s Station’, the Third Corps from Manassas Junction to Centreville; the Fifth Corps from Manassas Junction to Gum Springs; the Eleventh Corps from Centreville to Cow-Horn Ford, or Trappe Rock, on Goose Creek; and the Twelfth Corps from Fairfax Court-House to near Dranesville. The Cavalry Corps moved from Manassas Junction and Bull Run to Aldie.
One additional force, too small to mention in the itinerary, but which Butterfield noted in his letter to Pleasonton is worth mention. The regular engineer battalion, with bridging equipment, would move up to the Mouth of the Monocacy. Captain Charles Tunbull and his men were due to arrive the next day.
So as the sunlight faded 150 years ago today, the Army of the Potomac had two infantry corps and the cavalry corps camped in Loudoun, with two more corps just over the county line. The marches in Loudoun had just begun.
(Citations from OR, Series I, Volume 27, Part I, Serial 43, page 142; Serial 45, pages 151-2, 171, and 177.)
- Roads to Gettysburg – Marching through Loudoun (lccwrt.wordpress.com)
- 150 years ago: “We have had a severe fight” at Brandy Station (markerhunter.wordpress.com)