Action at Martinsburg

Thursday, July 11, 1861

On a hot July morning in 1861, a foraging expedition five miles from Martinsburg turned into a brief, deadly clash that left one Union soldier dead and two in Confederate hands.

  1. Narrative
  2. Opposing Forces
    1. Confederate
    2. Union
  3. Timeline
  4. Battlefield
  5. Location
  6. Primary Sources
    1. News Articles
    2. Reports and Letters
    3. Diaries and Memoirs
  7. Secondary Sources

Narrative

The Action at Martinsburg was fought on Thursday, July 11, 1861 between Union forces commanded by Col. John S. Clark and Confederate forces commanded by Capt. Thomas L. Yancey in what is today Berkeley County, West Virginia. The brief but inconsequential encounter highlighted the dangers of untested volunteers operating in enemy territory.

Acting under pressure from the War Department in Washington, DC, after one false start and with 90-day enlistments about to expire, scant artillery, and poor supply, 69-year-old Maj. Gen. Robert Patterson crossed the Potomac River at Williamsport, Maryland, on July 2, 1861. With an inexperienced and untested army, he stepped into Virginia to invade the lower Shenandoah Valley.

The Shenandoah Valley’s fertile farms and ironworks were vital to the Confederacy’s survival. At this early stage of the war, Confederate President Jefferson Davis entrusted its defense to Brig. Gen. Joseph E. Johnston, formerly the U.S. Army’s Quartermaster General. His Army of the Shenandoah included Col. Thomas J. Jackson’s brigade and Lt. Col. J. E. B. Stuart’s 1st Virginia Cavalry.

A single improved road ran from the ford opposite Williamsport up the Valley through Martinsburg, Winchester, and Harrisonburg to Staunton. The ninety-three-mile stretch of macadamized turnpike from Martinsburg to Staunton was known as the Valley Pike. When Patterson’s army crossed the Potomac, Jackson held Martinsburg ahead of the main Confederate force at Winchester. Martinsburg was also an important stop on the Baltimore & Ohio (B&O) Railroad.

In the late afternoon of July 2, Patterson’s leading brigades clashed with Jackson’s men along the road to Martinsburg in what became known as the Battle of Hoke’s Run, or Falling Waters. This delaying action allowed Jackson and Stuart to withdraw safely and rejoin Johnston. Patterson entered Martinsburg at noon on July 3, greeted by the cheers of its largely unionist population.

Meanwhile, Johnston assembled the Army of the Shenandoah for battle near the small village of Darkesville, about six miles south of Martinsburg, and remained there for four days before falling back to Winchester.

In Martinsburg, Patterson hesitated. His supply line from Hagerstown was stretched thin, and he believed Johnston outnumbered him. General Winfield Scott had warned him to “attempt nothing without a clear prospect of success,” and Patterson chose to wait for reinforcements. Col. Charles Pomeroy Stone, having completed his expedition along the Maryland shore of the Potomac, joined him on July 8 with elements of four regiments and a battalion of District of Columbia volunteers.

That same day, the 19th New York Infantry, the “Cayuga Regiment,” commanded by Col. John S. Clark, and the 28th New York Infantry, the “Scott Life Guard,” under Col. Dudley Donnelly, also arrived.

Patterson at last drafted orders to advance on Winchester but rescinded them at the last moment, citing the exhaustion of the newly arrived regiments. On July 9, he convened a council of war with his senior officers. They almost unanimously agreed the army was in a precarious position and ought to move farther east to Charlestown. Johnston might be luring them into a trap, and it seemed wiser to flank his position. Even so, Patterson remained in Martinsburg.

J. E. B. Stuart’s cavalry camped at Camp Vigilance near Bunker Hill, keeping the enemy under constant watch. Stuart kept Johnston informed of Patterson’s movements, harassed Union patrols, and drilled his men in tactics he had learned fighting the Apaches and Cheyenne.

Patterson’s army continued to suffer from shortages. He wrote to headquarters, “Supplies, especially provisions, are very scarce, and not even one day’s rations can be relied upon. The supply of grain also is very limited.” On the morning of July 11, Companies A and C of the 28th New York and four companies of the 19th New York, under Col. Clark, were assigned to guard a foraging expedition, with an eye toward catching some of the cavalry that had been giving them so much trouble.

The Harrisonburg Cavalry, led by Capt. Thomas L. Yancey, and the Washington Mounted Rifles, led by Capt. William E. “Grumble” Jones, were also active that morning. Yancey with 27 men, and Jones with 50, scouted in two separate parties toward Martinsburg.

A small group of soldiers from Company I, 19th New York, were foraging about two miles from camp when they spotted Jones’ horsemen and raced back up the road. Jones pursued with most of his force but sent five men, including Private John Singleton Mosby, around to cut them off. Mosby surprised and captured Corporal Martin Webster and Private Samuel J. Tobias, then rode to within sight of the Union camp before turning back.

Meanwhile, the main Union foraging party reached a farm about five miles southwest of Martinsburg. Capt. Elliot W. Cook, Lt. Daniel R. Whitcher, 20-year-old Private Isaac W. Sly, and five others from Company A, 28th New York, formed an advance guard to watch the road. Before long, they saw a body of cavalry approaching at full gallop and opened fire.

“About twenty of the scoundrels fired on us,” Yancey later boasted. “I made a charge on them, killed two, wounded one, and took a prisoner. The others retreated, and by the time his comrades came to his aid, [we] was out of the way.”

Cook’s party fell back toward their reserve, firing as they went. Private Sly was kneeling in a field to return fire when he was struck in the jaw; the bullet passed through his neck and killed him almost instantly. Another shot shattered the buckle on Lt. Whitcher’s scabbard.

By the time Col. Clark arrived with reinforcements, the Confederate cavalry had vanished over the horizon. Webster and Tobias were taken to Winchester for questioning, then sent on to Libby Prison in Richmond, where Tobias later died.

Shortly after returning from the foraging expedition, Clark was relieved of command and placed under arrest pending a court-martial. Several of his captains had accused him of “incompetency to command, harsh and ungentlemanly treatment of officers and men,” and frequent profanity. The charges were eventually dismissed, but he never again commanded a regiment.

Opposing Forces

Confederate

Lt. Col. J. E. B. Stuart, Commanding

UnitCommander(s)StrengthKilledWoundedCaptured
Harrisonburg CavalryCapt. Thomas L. Yancey28000
Washington Mounted RiflesCapt. William E. Jones50000

Union

Maj. Gen. Robert Patterson, Commanding

UnitCommander(s)StrengthKilledWoundedCaptured
28th New York Inf. Regiment, Co. A & CCapt. Elliot W. Cook100
19th New York Inf. Regiment, 4 CosCol. John S. Clark002*
* 2 captured from Company I.

Timeline

  • June 20, 1861 – Confederate Col. Thomas J. Jackson occupies Martinsburg with his brigade and destroys dozens of locomotives and train cars, burns round houses and machine shops, and tears up train tracks.

  • July 2, 1861 – Maj. Gen. Robert Patterson crosses the Potomac River near Williamsport for a second time, touching off the Battle of Hoke’s Run / Falling Waters / Hainesville.

  • July 3, 1861 – Patterson’s army occupies Martinsburg.

  • July 8, 1861 – Col. Charles Pomeroy Stone’s force from the “Rockville Expedition” joins Patterson at Martinsburg along with the 19th and 28th NY regiments.

  • July 9, 1861 – Patterson holds a council of war to decide whether or not to attack Confederate Brig. Gen. Joseph E. Johnston at Winchester. It is decided not to advance, thinking Johnston was luring them into a trap.

Battlefield

Contemporary accounts place this incident along the Valley Pike approximately 4.5 to 5 miles southwest of Martinsburg, which would put it near present-day U.S. Route 11 and Business Park Drive in Berkeley County, West Virginia. One source states that it occurred on the farm of someone named Sanders, but we have not been able to independently verify that detail or locate the property with certainty. There are no signs or markers commemorating the death of Private Isaac W. Sly.

Location

GPS Coordinates — 39.397, -78.002

Primary Sources

News Articles

Richmond Dispatch (Richmond, VA) 17 July 1861.

Buffalo Commercial (Buffalo, NY) 17 July 1861.

New York Times (New York, NY) 18 July 1861.

Richmond Dispatch (Richmond, VA) 23 September 1861.

Reports and Letters

Diaries and Memoirs

Patterson, Robert. A Narrative of the Campaign in the Valley of the Shenandoah in 1861. Philadelphia: John Campbell, 1865.

Trout, Robert J., ed. With Pen and Saber: The Letters and Diaries of J.E.B. Stuart’s Staff Officers. Mechanicsburg: Stackpole Books, 1995.

Secondary Sources

Boyce, Charles W. A Brief History of the Twenty-Eighth Regiment New York State Volunteers, First Brigade, First Division, Twelfth Corps, Army of the Potomac, From the Author’s Diary and Official Reports. Buffalo: The Matthews-Northrup Co., 1896.

Driver, Robert J., Jr. 1st Virginia Cavalry. Lynchburg: H.E. Howard, Inc., 1991.

Hall, Henry and James Hall. Cayuga in the Field: A Record of the 19th N. Y. Volunteers, All the Batteries of the 3d New York Artillery, and 75th New York Volunteers. Auburn: Truair, Smith & Co., 1873.

Thomas, Emory M. Bold Dragoon: The Life of J.E.B. Stuart. New York: Harper & Row, 1986.

Wilson, Gregory P. Private John S. Mosby, First Virginia Cavalry: Picketing Fairfax County Before Becoming the Confederacy’s “Gray Ghost.” CreateSpace: By the author, 2015.

Updated: 18 December 2025
Created: 28 November 2025