John Haslet was born in Ireland and trained for the Presbyterian ministry before settling in Delaware. He also practiced medicine and participated in colonial public life, experiences that gave him standing in the community before independence. In 1775 he served on Delaware’s Council of Safety, and in January 1776 he became colonel of the Delaware Regiment. The unit was raised for Continental service and quickly earned a reputation for discipline and effective battlefield performance.

Haslet led the Delaware troops during the New York campaign. At the Battle of Long Island, they fought with the Marylanders in the desperate effort to hold off British forces and protect the American withdrawal. The regiment later served at White Plains, where its steadiness again stood out during a difficult retreat. These actions came at high cost and under severe logistical strain, but they established the military reputation later associated with Delaware’s small Continental contingent.

Most of the regiment’s original enlistments expired in December 1776. Haslet nevertheless remained with Washington during the counteroffensive that began at Trenton. On January 3, 1777, at the Battle of Princeton, he was killed while helping rally American troops in close fighting. His death deprived Delaware and the army of an experienced commander at the moment Washington’s victories were restoring morale after months of defeat.

Haslet was first buried in the churchyard of the First Presbyterian Church in Philadelphia. In 1841, his remains were reinterred in Dover, and statesman John M. Clayton delivered a commemorative address. That transfer reflected a nineteenth-century effort to claim and honor Revolutionary memory at the state level. The grave therefore records both Haslet’s wartime sacrifice and the later process through which communities created public heroes, ceremonies, monuments, and historical narratives.

The marker at the Dover burial place summarizes a life that joined ministry, medicine, politics, and military leadership. It is not located where Haslet fought or died, but it provides a durable physical focus for remembering Delaware’s role in the Continental Army. His career also reveals how quickly civilians assumed command in 1775–1776 and how rapidly the war consumed them. Within one year of taking the regiment, Haslet had campaigned across several states and fallen at Princeton.

The reburial also shifted Haslet from a shared Philadelphia churchyard into a specifically Delaware memorial landscape. That act connected local identity to national independence and ensured that his name remained attached to the state he had represented, even though his campaigns and original burial extended beyond its borders.