The John Haslet home marker identifies the Milford-area landscape where one of Delaware's leading Revolutionary officers lived before the war. Haslet was born in Ulster around 1727 or 1728 and trained for the Presbyterian ministry. He immigrated to North America in the 1750s and gained military experience as a Pennsylvania provincial officer during the French and Indian War, including the Forbes expedition that captured Fort Duquesne in 1758. He later settled on a tract of more than four hundred acres near this road.

In Delaware, Haslet practiced medicine, farmed, and entered public life while raising a family. News of war transformed his career. On January 19, 1776, he was commissioned colonel of the newly raised Delaware Regiment. The unit, often called the Delaware Blues, grew to about eight hundred men and earned notice for discipline and appearance. Haslet's task included recruiting, equipping, training, and leading soldiers from a small colony suddenly required to contribute to a continental struggle.

The regiment joined Washington's army during the defense of New York. At the Battle of Long Island in August 1776, the Delaware troops fought beside Marylanders and helped cover the American withdrawal. They again resisted British attacks at White Plains in October. These battles were defeats for the Continental Army, but experienced units preserved cohesion under pressure. Haslet's men emerged with a strong reputation even as casualties, illness, desertion, and expiring enlistments steadily reduced their numbers.

Fewer than one hundred Delaware soldiers remained with Haslet by the end of the year. They crossed the Delaware River with Washington on Christmas night and participated in the victory at Trenton on December 26. That success revived an army and cause near collapse. A week later, on January 3, 1777, Haslet fought at Princeton. While attempting to rally troops during the confused action, he was shot in the head and killed. The American victory came at the cost of one of Delaware's most capable officers.

Haslet was first buried in Philadelphia. In 1841 Delaware reinterred his remains in Dover, and later memorials honored him at Princeton and in his home state. The regiment he organized continued under Colonel David Hall and became one of the Continental Army's respected formations before suffering devastating losses at Camden in 1780. Haslet's legacy therefore includes both his brief personal command and the military culture he helped establish.

The home marker links a national military story to the rural property from which Haslet entered service. Buildings and boundaries have changed, but the place recalls the civilian roles he left behind: immigrant, minister, physician, landholder, neighbor, and father. His life also shows how experience from Britain's earlier imperial war supplied leaders for rebellion. From this Milford-area home, Haslet moved into the central campaigns of 1776 and died just as the Continental Army recovered hope at Trenton and Princeton.