Westchester County, New York (which at the time also included all of present-day Bronx), played a unique role in the American Revolutionary War. From late 1776 to the end of the War in 1783, much of Westchester was a notorious no-man's land, known as the Neutral Ground, between the British Army and its auxiliaries on one side and the American Patriot forces on the other. Only the northernmost part of the county remained under more stable, though still contested, American control.

There were other areas during the Revolutionary War that shared similar characteristics or were locally referred to by the same name, such as northern New Jersey, southwestern Fairfield County, Connecticut,Greenwich, Connecticut, is also frequently included in historical and scholarly definitions of the Neutral Ground. While Connecticut was generally a Patriot stronghold, Greenwich's proximity to British-held Manhattan made it vulnerable to the same lawlessness as Westchester. parts of the Mohawk Valley, and regions along the southern frontier. None of these areas, however, was exposed to such a long period of high-intensity conflict and lawlessness as Westchester. In his seminal work, Westchester County during the American Revolution, 1775-1783, historian Otto Hufeland writes:In these seven years and four months, Westchester County was never free from the enemy—for every week and perhaps every day, it could furnish a record of bloodshed, either in open fight or in atrocious misdeed of sneaking robbers, and the strain of consuming anxiety was never absent from its people. They fought longer and suffered more than any other community in all the thirteen colonies...

The Armies

The first bloodshed of the war in Westchester took place on August 29, 1776, in Mamaroneck: Loyalist William Lounsbery (also spelled Lounsberry and Lounsbury), who was recruiting soldiers for the British side, was attacked and killed by a group of Patriots.Hufeland, p. 98: "…the first bloodshed in the county itself, occurred on August 29th, 1776, when a party of Americans surprised and attacked…a meeting of 14 loyalists at Mamaroneck, wounding one of them, Bloomer Nelson, and killing their leader, William Lounsberry, an active and enterprising tory, in whose pockets a warrant to enlist men for Colonel Robert Roger's Rangers, together with a list of those already enlisted, was found." Later that year, after a strategically important skirmish at Pell's Point, a major battle between the British Army, led by General William Howe, and the Continental Army, commanded by General George Washington, was fought at White Plains, in the heart of Westchester. The Battle of White Plains (October 28, 1776) was the last opportunity for the British to trap Washington's army and potentially end the American rebellion in its first year. While a tactical victory for Britain, the battle's long-term significance lies in Washington's ability to preserve the Continental Army and keep the Revolutionary cause alive.

Following the Battle of White Plains, the Continental Army was forced to retreat north. Its primary headquarters was established north of Peekskill at Continental Village,Then part of the South Precinct of Dutchess County, now in Putnam County. just outside the northern Westchester border. The British were headquartered in New York City, controlling the entire island of Manhattan. The heavily contested, roughly 15-by-30-mile (150-square-mile) "neutral" zone between the permanent defensive lines of the two armies spanned from the Croton River down to the British forward outposts in present-day Bronx neighborhoods of Kingsbridge and Morrisania; it encompassed almost all of Westchester.

Notable military engagements in the Neutral Ground during the war included the skirmishes at Mamaroneck, Edgar's Lane, Pound Ridge, Young's House, Pine's Bridge, and Van Cortlandt's Woods. The Royal Navy frequently used its warships in the Hudson River to support land operations in Westchester; historical markers along the Westchester coastline commemorate the Action at Tarrytown, the Defense of Teller’s Point, and other naval engagements.

In July-August 1781, both the Continental Army and the allied French army under Jean-Baptiste de Rochambeau marched through Westchester before joining forces at Dobbs Ferry. The combined Philipsburg Encampment of the two armies stretched for miles from North Castle/Mount Kisco (east) to the Hudson River, and from the Croton River (north) toward White Plains and Dobbs Ferry. Rochambeau's army was headquartered at the Odell House in present-day Hartsdale, while George Washington's headquarters were located near present-day Ardsley High School. The joint encampment was a key strategic point for launching the Yorktown campaign.

At the outset of the Philipsburg Encampment, on July 3, Washington and Rochambeau attempted a secret night operation to seize British outposts at Kingsbridge. The attempt failed.Experiencing the Neutral Ground of the American Revolution / The McDonald Interviews: Timeline Guide. Westchester County Archives. pp. 36-37. Later that month, Washington issued an order "For Reconnoitering the Enemy's Post at the North end of York Island and the vicinity of it." This reconnaissance-in-force against British-held New York City was conducted on July 21-23, 1781, and became known as the Grand Reconnaissance. It involved between 4,000 and 5,000 American and French troops who marched south on separate local roads, including the Saw Mill River Road and the Tuckahoe Road. While Washington and Rochambeau’s soldiers paraded before the British lines and conducted feint attacks on the British works, the French military engineers mapped out enemy fortifications. The results of the Grand Reconnaissance were conclusive: the British used their five years in Manhattan to heavily fortify the city, and attacking it would have been a disaster. On August 19, 1781, the Continental Army broke camp and assembled in Dobbs Ferry.Just east of the modern Broadway-Ashford Avenue intersection. After being "paraded for the march," the troops moved north on Broadway toward the Hudson River crossing at King's Ferry on Verplanck's Point in northwestern Westchester. From there, they would cross the river to Stony Point and embark on their southward march to Yorktown, Virginia.

Parts of the Continental Army marched through Westchester County again in 1782 during their return to the Hudson Highlands from the Yorktown campaign. In August 1782, Washington moved approximately 8,000 men by boat from West Point down the Hudson River to Verplanck's Point. This move was specifically planned to meet the French as they marched north from Virginia. The two armies reunited at Verplanck's Point in September 1782. This deployment kept the Continental Army closer to British-occupied New York City while they waited for final peace negotiations to conclude. On September 14, 1782, Washington staged a review of the Continental Army at Verplanck's Point as an honor for the departing Rochambeau and his French troops.

Loyalists and Patriots

Unlike the "hotbeds of radicalism" in New England, the general population of Westchester before the war was characterized by a conservative, agrarian outlook. The upper classes were divided between Patriot and Loyalist sympathies, with Loyalists (or Tories, as they were called by Patriots) constituting "a substantial minority."Hufeland, p. xiv. The leading Loyalist in the Province of New York was Samuel Seabury, rector of an Anglican parish in lower Westchester County, who wrote fiery anti-rebellion pamphlets under the pen name A. W. Farmer (standing for "a Westchester farmer"). Members of Westchester's most prominent families, despite being closely related, were on opposite sides: the Philipses of Philipsburg Manor were unyielding Loyalists, while the Van Cortlandts of Van Cortlandt Manor were prominent leaders for the Patriot cause.

At Philipse Manor Hall (in what is now Yonkers), British General Henry Clinton in the summer of 1779 wrote the Philipsburg Proclamation, which declared all Patriot-owned slaves to be free and that blacks taken prisoner while serving in Patriot forces would be sold into slavery. Westchester's Black Loyalists, along with numerous white Loyalist refugees, fled the Neutral Ground for British-occupied Manhattan and Long Island.Before being evacuated to Canada's Nova Scotia and New Brunswick at the end of the war. There, Westchester refugees formed Loyalist military units. Local historian Henry Steiner writes: "The character of the fighting in Westchester County was as much that of a civil war as it was a war for independence."

Major Loyalist military units operating in the Neutral Ground included Queen's Rangers (or Rogers' Rangers), Emmerick's Chasseurs (commanded by German soldier Andreas Emmerich who would later write a manual on guerrilla warfare, The Partisan in War), Skinner's Greens or Skinners (the term "skinners" was also applied to all maraudering bands, including Patriot-aligned guerrilla groups), De Lancey's Brigade (commanded by Oliver De Lancey), and De Lancey's Cowboys (often called simply "the Refugees" by the locals; this much-hated unit was commanded by James De Lancey, Oliver's nephew). They were engaged in military raids as well as in looting and cattle raiding, for which De Lancey's Cowboys were particularly notorious.James De Lancey was second cousin of Philip Van Cortlandt, who was Brigadier General in Washington's Continental Army.

The majority of local residents–from tenant farmers to storekeepers to freeholders–remained apolitical and nonpartisan until the conflict physically arrived at their doorsteps. "The mixed political outlook of the population, with some initial opposition to the Revolution and a strong sentiment of neutrality, meant that the Patriot government could not automatically count on community support in efforts to stabilize the region." Eventually, however, a significant part of the populace joined the fight against the British. "Until the march of the British through the County and the Battle of White Plains, the lines between the political parties were not sharply drawn and only after personal suffering from continued raids did that bitterness develop that remained till after the close of the war and eventually made the farmer boys of Westchester a match for the best British light troops and the raiding bands of the native Refugee cowboys..."Hufeland, p. 76.

The newly converted Patriots (or Rebels, as they were called by the Loyalists) joined Westchester militia regiments. These units were part of the state militia whose main function was guarding the area, but they would later frequently serve with the Continental Army in military operations. In January 1777, General William Heath asked the Westchester Committee of Safety for local men to help the army navigate the famously difficult Westchester terrain. This led to the formation of the Westchester Guides, an elite group who served as pathfinders, scouts, and advisors for high-ranking officers and became essential fixtures in virtually every Continental Army operation within the county. Some of the Westchester guides, such as Abraham "Brom" Dyckman and Cornelius Oakley, commanded their own units of irregular cavalry, conducting raids against Loyalist regiments and irregulars, provisioning American troops, and gathering military intelligence for the Continentals.

The Whaleboat War (1776–1783) heavily featured activities in Westchester County's "neutral" waters, particularly in the Long Island Sound and the Hudson River at the Tappan Zee, where both Loyalist and Patriot boat crews engaged in smuggling, warehouse raiding, and small-boat warfare. Communities around New Rochelle, Harrison, and Rye frequently faced maritime raids, with homes broken into and goods stolen by crews coming from Long Island or Connecticut.