By the summer of 1780, the northern theater of the American Revolution had been reduced to raids and minor skirmishes. The Battle of Monmouth in June 1778 was the last significant engagement in the region. George Washington's army had settled into a blockade around British-held New York City, and the war's center of gravity had shifted south to Charleston and the Carolinas. British commander Sir Henry Clinton had taken 8,700 troops to South Carolina, leaving Wilhelm von Knyphausen to hold New York with 10,000 soldiers. Knyphausen had recently been repulsed at the Battle of Springfield in New Jersey. Washington, needing to cover West Point while waiting for a promised French fleet, found his army short of almost everything, including food. The British kept cattle and horses on Bergen Neck, across the Hudson from Manhattan, protected by a small stockaded blockhouse at Bull's Ferry manned by Loyalists under Thomas Ward.

Washington ordered Wayne to take the 1st and 2nd Pennsylvania Brigades, four artillery pieces, and Stephen Moylan's 4th Continental Light Dragoons to destroy the blockhouse. But the blockhouse was only half the mission. Wayne sent his cavalry under Major Henry Lee III to round up the British livestock on Bergen Neck while he took three regiments and the artillery to deal with the fortification. The split mission reflected Washington's practical priorities: the Continental Army needed food as badly as it needed victories. Lee's dragoons moved south toward the cattle while Wayne positioned his guns to bombard the stockade. The two prongs of the operation would have very different outcomes.

Early on July 21, Wayne opened fire with his four cannons. An hour of bombardment produced no discernible results against the log fortification. Meanwhile, the Loyalists inside poured accurate fire through their loopholes. Soldiers from the 1st and 2nd Pennsylvania Regiments, frustrated by the ineffective bombardment and stung by the return fire, lost patience. Despite their officers' attempts to restrain them, they charged forward through the abatis, the sharpened wooden obstacles ringing the stockade, and reached the base of the walls. There they discovered what their artillery had already demonstrated: the position was too strong to breach. Unable to break through, the Pennsylvanians were forced to retreat under fire. Wayne reported 15 enlisted men killed and three officers and 46 men wounded. Clinton admitted the loss of 21 Loyalist casualties and noted that 50 round shot had penetrated the blockhouse without bringing it down.

While Wayne's infantry bled at the stockade, Lee's cavalry succeeded at the cattle drive. The seizure of British livestock was the operation's one concrete achievement, and it gave Andre his material. The Cow Chace opened with Wayne as a comic figure: "To drive the kine one summer's morn, / The tanner took his way; / The calf shall rue that is unborn, / The jumbling of that day." Andre lampooned Wayne and Lee as drovers rather than soldiers, credited a subordinate officer with command of the actual assault, and took shots at Lord Stirling's well-known drinking habits. The final stanza feigned fear of Wayne's retribution: "And now I've clos'd my epic strain, / I tremble as I show it, / Lest this same warrior-drover, Wayne, / Should ever catch the poet." Wayne never did catch the poet, but the war did. On October 2, 1780, barely two months after writing The Cow Chace, John Andre was hanged at Tappan, New York, for his role in Benedict Arnold's plot to surrender West Point to the British.