The Numerical Strength of George Washington’s Army During the 1777 Philadelphia Campaign

Introduction

Perhaps the most important facet for understanding and appreciating a military campaign is a solid grasp of the composition of the armies engaged in it; the quantity of troops shares equal importance to the identity and quality of them. The multitude of books and monographs dedicated to the 1777 Philadelphia campaign, whether in part or in entirety, estimate American troop strength because no army returns between September 1 and October 4 (the primary period of battles) were known to exist. That glaring deficiency has come to an end—at least partially. Two Continental infantry numerical strength reports have recently been unearthed from the papers of Timothy Pickering, the American adjutant general during the campaign. One tallies the entire army’s Continental infantry in early September; the other does likewise near the end of the month. When combined with known returns for the beginning of November and December, these new discoveries not only fill a gap with two absolutely necessary time points, they also provide a trend line to understand how the size of the army changed during the course of the four-month campaign.

Sources and Methods

Numbers obtained from six returns develop the size of the American army in Delaware and Pennsylvania between August and December 1777.[1] Only two of those returns have been previously published. During the American Revolution Bicentennial, Charles Lesser included the November 3 weekly return and the December 2 monthly troop-strength reports in Sinews of Independence, an anthology of mostly monthly returns primarily obtained from the National Archives.Those two returns depict Continental infantry numerical strength at the brigade level. They are complete for field, staff, and non-commissioned officers fit for duty, as well as both present and absent rank and file (privates) subdivided into several categories.

The lacunae of troop-strength reports between May and November has forced historians to merely estimate the size of Washington’s army during the most active portion of the Philadelphia campaign waged halfway between that yawning gap of known returns. Col. Timothy Pickering, the adjutant general of the army from June 1777 through January 1778, kept a copy of the December 2 return, but his copy also included a partial militia report and a Continental artillery return.

Most importantly within Pickering’s collection is a revealing summary of the troop-strength return of Continental infantry ordered on September 1 and completed on September 3, as well as one reported on September 24. Unlike the brigade-level reports in November and December, these two September returns summarize the numerical strength of the total Continental infantry present, and include the total of the same officer and rank and file subdivisions that appear in the brigade-level reports later in 1777. These two returns capture the numerical strength of Washington’s infantry the week before the battle of Brandywine while the army encamped in Delaware (September 3), and reveal the size of the force three weeks later (September 24)—after the Battles of Brandywine and Paoli, but only ten days before the battle of Germantown.

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The September 3 return includes all ten brigades organized within five infantry divisions of the Continental army and also includes Brig. Gen. Francis Nash’s North Carolina brigade. Two light infantry forces, one present and one absent, both indirectly appear on this return within a catchall category of infantry called “on command.” The absent force, Col. Daniel Morgan’s Virginia riflemen—estimated at 400 rank and file—were detached to the Northern Department to reinforce and assist Maj. Gen. Horatio Gates. The brand new and present force of light infantry commanded by Brig. Gen. William Maxwell was carved equally out of nine brigades. A total force of 800 rank and file is estimated for this unit; 900 including officers.

The total “on command” category on the September 3 return numbers 2,382 infantry privates, 1,182 unaccounted for after separating out the light infantry. These remaining “on command” troops are rank and file soldiers, fit for duty, but temporarily not attached to their respective regiments. In 1778, the adjutant general determined that 58 percent of the unaccounted in this column were encamped with the army serving as artificers or assisting other commands, but available for service in the event of an emergency (on September 3 this amounted to 685 privates in addition to the 800 light infantry present).[2] Similarly, 67 percent of soldiers columned as “sick present” were deemed by the adjutant general as healthy enough to fight if surprised by an enemy assault.[3] Obviously, soldiers appearing in the “sick absent” and “on furlough” columns were not present with the army. Forty-two percent of the unaccounted “on command” soldiers on any given return were considered detached too far from the encampment area to be relied upon for emergency service.

Estimating Missing Data

While commissioned and non-commissioned company and regimental officers are tallied on two September returns and on the November and December ones, missing from all September returns are officers categorized as “staff” (for example, chaplains, paymasters, adjutants). This is a consistent total tally based on subsequent returns, so the November 3 total of 206 for the same regiments and brigades serving Washington in September was applied to those two returns as well. Brigade, division, and army personnel are not tallied in any returns.  This includes generals (and colonels commanding brigades) and their respective military families. An added factor of 100 minimally adjusts for these key personnel from September through November, and 150 for December, a month with seventeen brigade commanders and five major generals. (for example, George Washington’s headquarters exceeded fifteen officers for most of this period; neither he nor anyone on his staff had ever been considered in these returns.)

Another category of missing officers in every return is “sick present” officers and those “on command” that remained on location with the army. On 1778 returns these officers were routinely tallied, and numbers exceeding 500 were present in most of those returns. No trend can be identified in the 1778 data to estimate their numbers during the Philadelphia campaign; for this reason they are entirely omitted which assures an underestimation of the true present strength of the army.

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No return previous to December 1777 has yet been discovered that captured the number of Continental dragoons and artillerists serving with Washington. December tallies of 497 horse soldiers and 620 cannoneers equates to 1,120 non-infantry Continentals. This value was applied to the September and November returns as a minimal estimate of their strength, figuring that any reinforcing artillery that arrived with the transferred brigades of the Northern Department were more than offset by the losses incurred at Brandywine, Paoli, and Germantown. Although complete militia numbers are not available in these returns, partial numbers are presented in some of them and a reasonable estimate can be determined from additional sources.

No return exists for August 1, 1777, the first morning in 1777 that most of the available Continental army awoke on the Pennsylvania side of the Delaware River. This force amounted to all but one available battery of Continental artillery, all Continental dragoons, and seven and a half brigades of Continental infantry—two regiments short of four complete divisions. Sullivan’s two Maryland brigades stood six days’ away by hard marching, while Nash’s brigade and a battery of artillery were within a two-day march of uniting with the main army. Therefore, a reasonable estimate of numbers available on August 1 can be derived by an appropriate fraction of infantry from the September 3 data. This estimate is important to appreciate what Washington readily had available to defend against Howe’s 16,000-man army had the British commander chosen to ascend the Delaware River once he entered the Capes on July 30. This method necessarily assumes no net change of numerical strength throughout August which produces a clear overestimate of the true size of the August 1 force because there is no way to capture the net gain of enlisted soldiers over departed ones that month in an army that tarried in camps for three weeks and fought no battle during that span.

It is important here to distinguish between an encampment force, a force under attack, and an attacking force. By our definition an encampment force (for example, the one in White Marsh on December 3) includes all present troops within two miles of the main army by foot and five miles by horse. This includes all present officers, all fit for duty and present sick rank and file soldiers, as well as 58 percent of the unaccounted “on command” column. The difference between the encampment and defending force (for example at the Battle of Brandywine, September 11) is a removal of one-third of the “present sick” column which is deemed too sick to participate in a battle, even close to where they are encamped. Finally, an attacking force (for example, at the Battle of Germantown, October 4) differs from a defending force in the assumption that no “present sick” soldiers, no “staff” category of officers, and only 40 percent of the unaccounted “on command” column is healthy and available to participate in an extended march and assault upon an enemy position.

Table 1 incorporates the newly-discovered September returns to capture the encampment strength of George Washington’s army at three time points. The left-side column estimates the size of the force on the morning of August 1 twenty miles north of Philadelphia, the day after the bulk of his army crossed the Delaware River at Coryell’s and Howell’s ferries. The middle column captures by both official tally and estimates the army near Wilmington on the morning of September 3, 1777. This date is the day of the first engagement at Cooch’s Bridge but also is the first day in the campaign the entire army was united in the same theater. The right-side column captures the numerical strength of the army while most of it was encamped north of Swamp Creek, near Fagleysville, Pennsylvania, and depicts the same regiments three weeks after the Delaware encampment, revealing the effects of battles and heavy marches upon its numerical strength.

Table 1:  Numerical Strength of Washington’s 1777 Army: From Crossing the Delaware Through the Battle of Paoli

Assessment

If General Howe had unhesitatingly ascended the Delaware River beginning on July 30, he could reasonably have disembarked his entire force at Wilmington between August 1 and August 3, and begun a twenty-six mile march to Wilmington with between 16,000 and 17,000 officers and men. The size of his army alone would have dominated Washington’s readily available force of fewer than 10,000 soldiers in all arms. Howe’s decision to abandon the Delaware and ascend the Chesapeake allowed Washington an additional month to field nearly twice as many men as he had had on August 1. When Howe began his direct assault against Maxwell’s light infantry at Cooch’s Bridge on September 3, 1777, George Washington outnumbered Howe in the Maryland/Delaware theater.

Although not depicted in the table, the number of American soldiers present to fight at the Battle of Brandywine on September 11 was reduced by 2,000 militia (only 3,000 Pennsylvania militia positioned themselves at fords to defend this day),[4] and 200 fewer Continental infantry compared to September 3 as these men were calculated to be too sick to participate. These adjustments still leave a considerable force of 12,400 infantry, 1,120 cavalry and artillery, and 3,000 militia for a total defending force of 16,520 officers and men present to fight at Brandywine. This new tally is surprisingly close to a recent estimate provided in a book-length treatment of this battle.[5]

Battle casualties at Cooch’s Bridge, Brandywine, and Paoli, as well as 150 miles marched in a span of twelve days, including a day subject to the most intense rainstorm of their lifetime, provided several reasons for at least the temporary loss of nearly 2,200 Continental infantry officers and men between September 11 and September 23.

October 1 Army Strength

With the discovery of two army strength returns for September 1777 in Pickering’s papers, not only can we calculate a more accurate force strength for Brandywine, but also for the Battle of Germantown. Additionally, Washington provided specifics about his rank and file present and fit for duty at a September 28 council of war, perhaps as a summary of a special field report which has yet come to light. Direct and derived data from the September 24 field return and the September 28 record from a council of war provides 12,602 battle-ready troops with the army camped near Faulkner’s Swamp ten days before the battle of Germantown. Missing from that return is Potter’s Pennsylvania militia brigade, artillery and dragoons. Also not included are the New Jersey and Maryland militia that would join the army prior to Germantown. These “missing” units added another 3,720 battle-ready troops to Washington’s army. By October 1, Washington had 16,322 battle-ready troops for an attack on the British camp at Germantown, some 2,000 more than the estimate in a recent study of the battle.[6]

Table 2: Numerical Strength of Washington’s Army on October 4, 1777: Battle of Germantown

Analysis

The difference between the battle-ready force at Brandywine versus Germantown was 198 fewer soldiers in the latter battle. George Washington’s army suffered 1,700 casualties at Brandywine, the Battle of the Clouds, Paoli and other minor skirmishes over those three weeks. Also, approximately 1,000 Pennsylvania militiamen either went home at the end of their terms or deserted over that same time span. Therefore, Washington had a total loss of 2,700 troops prior to Germantown. During this span, Washington added 2,800 troops from the Connecticut Line (Brigadier General Alexander McDougall’s brigade) plus New Jersey and Maryland militias. Washington should have had a net gain of 100 troops but the returns tell us he had about 200 fewer troops for Germantown. Why? That net loss could plausibly be explained by the difference of more “sick present” soldiers who could shoulder a gun in defense at Brandywine but could not be expected to conduct an overnight march to launch an attack at Germantown. Regardless, this tally of Washington’s Germantown force is considerably higher than any previous estimate regarding this battle.

What Else Do These Numbers Show Us?

Well known and understood is the direct detrimental effect of battle losses on the strength of an army during a campaign, both in crushing defeats and in pyrrhic victories. Underappreciated is the potential crippling effects of desertions. Even wildly successful forces are not immune to this. For example, in the midst of his world-famous Shenandoah Valley Campaign of the Civil War, Gen. Thomas J. Jackson’s namesake Stonewall Brigade shrunk 55 percent after losing 2,000 soldiers in twenty days of marching—but without fighting any battle in that span.[7] Those men, mostly new recruits, permanently deserted from a successful army.

What impact did Washington’s failures throughout the Philadelphia campaign have on desertion, particularly the 2,800 temporary and permanent losses of officers and men in battle (Cooch’s Bridge, Brandywine, Battle of the Clouds, Paoli and Germantown)? One might suspect that this series of defeats would swell desertion rates for several weeks after the last of those battles (Germantown, October 4). Unfortunately, neither desertions nor recruits were tabulated in extant army-sized returns in 1777.

Regardless, Table 3 attempts to capture the effects of desertions by trending the numbers of men in Continental infantry regiments present (and absent) in the first days of September and following the same units for three months into early December. Since complete data for present and absent soldiers exists only for rank and file foot soldiers, and since privates represent the bulk of Washington’s army, only this category of infantry is tabulated:

Table 3: Numerical Strength of Continental Rank and file Infantry at Four Time Points

The lowest total (last column) and present numbers as well as the highest absent numbers appear in the September 24 row; this is most likely a result of battle casualties as well as straggling and dispersed troops in the wake of the heavy marching between September 14-23. A noticeable improvement in all rows transpires over the subsequent ten weeks, even after suffering severe casualties at Germantown. This could be explained by a return of previously wounded soldiers combined with an influx of new recruits. Considering that total killed and captured infantry privates between September 1 and December 1 exceeded 1,000, then Washington’s army enlisted at least 700 more rank and file soldiers than it lost by desertions or discharges during those three months. It is clear from the above table that new recruits during an active, losing campaign were surprisingly many, while desertions and discharges were certainly not detrimental at all, and may have been so insignificant as to be negligible. As catastrophic as the Philadelphia campaign outwardly appeared—it certainly injured Washington’s reputation and ultimately spawned the infamous Cabal—that negative outcome in the theater, combined with escalating and crippling deficiencies in the commissary and quartermaster departments, surprisingly had no measurably adverse effect on desertions in Washington’s army during the autumn months of 1777.

November 3 to December 2 Army Strength

A weekly return for Washington’s army was completed on November 3, 1777 and a monthly return was reported out on December 2. Determining the strength of Washington’s force for early November requires some decisions. By this point in the campaign, fighting was raging along the Delaware River necessitating the detour of reinforcements from the north to the river forts and detachments from the main army to operate along the river. Additionally, New Jersey militia did not migrate to Whitemarsh; instead, they moved into position in support of the river operations in southern New Jersey. As Washington was forced throughout October and November to make decisions about weakening the main army for the river operations — and harbored hopes of attacking William Howe in Philadelphia again — we have chosen to analyze the total force available for Washington in the Philadelphia region.

The November 3 weekly return delineates 12,592 troops in the Whitemarsh encampment. Missing from that return are two Rhode Island regiments garrisoning Fort Mercer. Also missing are the Pennsylvania and Maryland militia serving with the main army and the New Jersey militia operating in southern New Jersey. Dragoons and artillery are also absent from the return. Therefore, 5,170 “missing” men need to be added. In total, Washington had a force of 17,762 men operating in the Philadelphia region in early November 1777.

From the December 2 return, we can determine the strength of the army for the Whitemarsh operation as the abandonment of the forts in mid-November resulted in the concentration of the army here. The return lists 23,227 troops in the Whitemarsh encampment.  Missing from that return are the dragoons and artillery, but a December 2 artillery return exists in Timothy Pickering’s papers. A dragoon total can be estimated from the December 31 monthly return. With all soldiers accounted for, George Washington’s army at Whitemarsh numbered 24,597 officers and men in all arms.

Table 4: The Army at Whitemarsh: Present in Camp, November 3-December 3, 1777

Analysis

Washington’s army suffered about 1,100 casualties at Germantown, Fort Mercer, and other minor skirmishes over the month of October. The only new units to join the army over that same time period were the two Rhode Island regiments. The army should have shown a net loss of 600 men between October 1 and November 3, but the returns tell us they actually gained over 600 men. Why? An impressive surge of recovered sick and wounded officers and privates as well as new recruits populated the army; this trend dovetails well with the rank and file data (see Table 3). The 17,762 men operating in the Philadelphia region on November 3 were not necessarily all attack ready, but they were present in the various camps.

Between November 3 and December 2, Washington gained 6,835 more men in one month. Considering the army suffered about 120 casualties at Fort Mifflin and other operations during this period, how did this happen?  Five infantry brigades and eight independent regiments reinforced Washington from the northern army. These units added 6,712 men to Washington’s force. Washington actually added 123 more men than that, which can easily be explained by the artillery batteries that came with those brigades from the northern army.

The massive army Washington perched twenty miles north of Philadelphia three weeks before the start of winter outnumbered General Howe’s by 50 percent. Washington augmented his force from the victorious northern army to attack his enemy with it. On November 24, he held a council of war with subordinate officers to consider an attack plan devised by Brig. Gen. John Cadwalader of Philadelphia, and on December 3 he requested from his brigadier and major generals their input regarding “the Advisieability of a Winters Campaign, & practicality of an attempt upon Philadelphia.”[8] General Howe’s foray from Philadelphia to challenge Washington at Whitemarsh during the close of December’s first week disrupted Washington’s plan to attack him, but it did not vanquish it.

December 18 Army Strength

It is instructive to look at Washington’s strength the day before the Valley Forge “march in.” Army strength for December 18 while they were still camped at “the Gulph” can be determined from the five known returns for the army from December—monthly returns compiled on December 2 and December 30, weekly returns completed on December 4 and December 22, and a special field report conducted on December 23.[9] An analysis of these returns tells us that Washington had 20,480 attack-ready troops and a total encamped force of 24,257 one day before entering Valley Forge.

Table 5: December 18 Army Strength at “the Gulph” prior to Valley Forge “march-in”

Analysis

Over the course of two weeks, Washington’s total present force decreased by 340; upwards of 300 of them can be explained by casualties at Whitemarsh, Matson’s Ford, and other minor skirmishes. The undetected shift of one additional percent of “on command” troops to extra-duty service outside camp can easily explain the remainder.

Although the Gulph encampment existed a mere five miles from Valley Forge, 24,000 American soldiers did not transfer to the winter encampment the following day. The two Maryland Line brigades and all the militia did not participate in the “march in” on December 19—leaving about 19,000 troops to arrive with Washington at Valley Forge.

Notwithstanding his preparation for a winter encampment at Valley Forge for most of his army and Wilmington for his two Maryland brigades, Washington continued to seek an avenue to use his dominating numbers to attack General Howe. This included a December 23 surprise offensive against a large British foraging force, and a full-scale Christmas-time assault on Philadelphia.[10] Neither planned offensive came to fruition due primarily to quartermaster and commissary deficiencies.

Conclusion

Newly discovered late summer and autumn 1777 returns provide crucial data regarding George Washington’s army during the Philadelphia campaign. A dedicated core of eleven infantry brigades remained intact despite several battlefield losses, all the while gaining defensive and offensive battlefield experience as it was buttressed by six more brigades later in the campaign. Not only did George Washington outnumber William Howe early in September, the late September through late November reinforcements and new recruits which swelled his ranks gifted Washington with an impressive-sized army that continued to field more soldiers than the British, and eventually an army awesome in size. From Whitemarsh to the Gulph throughout the first two weeks of December, George Washington operated the largest active, single-region field army on the face of the earth, a force in numbers that exceeded the British army in Philadelphia by 50 percent—8,000 soldiers—and exceeded the civilian population of New York, then the second largest city in the United States of America. Numbers were not the only requirement for the precise, perfectly-timed offensive that Washington sought, but the stunning size of his army provides a counter to twentieth and twenty-first century critics of Washington’s mindset who belittled his late December plans to assault of Philadelphia as “a holiday-induced overindulgence in hemp or Medeira at HeadQuarters.”[11]

[1]November 3 and December 2 return in Charles H. Lesser, ed.,The Sinews of Independence: Monthly Strength Reports of the Continental Army(Chicago: University of Chicago Press, 1976), 50-53; September 3 and 24 returns, Timothy Pickering Papers, Massachusetts Historical Society, Boston Massachusetts; undated late September 1777 field return cited in “Council of War,” September 28, 1777, in Philander D. Chase, ed., The Papers of George Washington, Revolutionary War Series (Charlottesville: University Press of Virginia, 2001), 12:338-39 (PGW); December 22, 1777 Weekly Report, www.fold3.com/image/9151405.

[2]May 2, 1778 Weekly Report (cover), www.fold3.com/image/9151560.

[3]Ibid.

[4]John Armstrong to Thomas Wharton, September 8, 1777 in Samuel Hazard, Pennsylvania Archives, Volume 5 (Philadelphia: Joseph Severns & Co., 1853), 598.

[5]Michael C. Harris, Brandywine: A Military History of the Battle that Lost Philadelphia but Saved America(El Dorado Hills, CA: Savas Beatie, 2014), 368.

[6]Michael C. Harris, Germantown: A Military History of the Battle for Philadelphia, October 4, 1777 (El Dorado Hills, CA: Savas Beatie, 2020), 193.

[7]Total desertions calculated from official returns. See Gary Ecelbarger, Three Days in the Shenandoah: Stonewall Jackson at Front Royal and Winchester(Norman, OK: University of Oklahoma Press, 2008), 34.

[8]“Brigadier General John Cadwalader’s Plan for Attacking Philadelphia,” c. November 24, 1777, PGW 12:371-373; “Circular to General Officers of the Continental Army,” December 3, 1777, PGW 12:506.

[9]December 2 return in Lesser,Sinews, 52-53; December 4 Weekly Report, www.fold3.com/image/9151401; December 22, 1777 Weekly Report, www.fold3.com/image/9151405; Field Return, December 23, 1777, www.fold3.com/image/9151423; copy of December 31, 1777 return, www.fold3.com/image/9151410; also see Lesser, Sinews, 55.

[10]George Washington to Henry Laurens, December 23, 1777 PGW 12:683-87; “Plan to Attack Philadelphia,” PGW 12:701-703.

[11]Wayne K. Bodle and Jaqueline Thibault,Valley Forge Historical Research Report(Washington, D.C.: United States Department of the Interior, 1980), 127.