In June 1780, George Washington’s main army was recovering from the severe winter encampment at Morristown. British and Hessian commanders in New York believed the Continentals were weakened by shortages, expiring enlistments, and discontent. Lieutenant General Wilhelm von Knyphausen launched an invasion from Staten Island, hoping to move through New Jersey toward the supply base and army positions around Morristown. The route required passage through communities east of the defensive Watchung Mountains.

The invaders landed near Elizabethtown during the night of June 6–7 and advanced toward Connecticut Farms, the settlement now within Union Township. New Jersey Continental troops and militia contested the roads and bridges, delaying a force much larger than their own. Fighting and withdrawal carried through the village. Homes were plundered or burned, and civilian Hannah Caldwell was killed, an event that quickly became a powerful Patriot symbol even as details of the shooting remained disputed.

Knyphausen halted without reaching the critical Hobart Gap and withdrew toward Elizabethtown. On June 8, Washington established headquarters at the location commemorated by this marker. From the Connecticut Farms area he could follow the retreat, coordinate the New Jersey defense, receive intelligence, and remain close enough to respond if the British renewed their advance. A field headquarters brought staff officers, couriers, guards, maps, and written orders into a place briefly central to the army’s decisions.

The British threat did not disappear. Forces remained near Elizabethtown, and on June 23 another invasion produced the Battle of Springfield. Continental units and militia again blocked the route through the Watchungs, and the British finally returned to Staten Island after burning much of Springfield. The two June actions were among the last major battles in the northern theater. They showed that New Jersey’s militia and regular forces could still mobilize effectively after years of war.

The marker identifies Washington’s headquarters on June 8 rather than claiming that the site was his permanent residence. Headquarters in an active campaign could shift rapidly as armies marched and information changed. The location’s importance comes from its position immediately after the Battle of Connecticut Farms, when Washington moved closer to the contested corridor and supervised the response. It connects a specific command decision with the larger defense of northern New Jersey and the failure of Britain’s final serious attempt to reach Morristown.

The older name Connecticut Farms is essential to interpreting Revolutionary sources, because Union Township was created later. Recognizing the name change connects period maps and reports to the present municipality. The marker performs that translation directly, allowing a modern street corner to be read within the 1780 campaign landscape.