John Philip De Haas was born c. 1735 in Holland (now Netherlands). He was the son of John Nicholas De Haas, a descendant of Baron Charles De Haas of Brandenburg, Prussia, and later of Strasbourg, Alsace, who is said to have received the family arms - those of the city of Florence - from Emperor Rudolph as a reward for services in the conquest of Italy. The parents of John Philip emigrated to America about 1737 and settled in Lancaster County, Pennsylvania.
Practically nothing is known of De Haas' early life prior to his entry into the military service. He was commissioned ensign of the Provincial Battalion of Pennsylvania in December 1757, and was stationed at Fort Augusta on the Susquehanna River. In 1758 he participated in the Forbes expedition against the French at Fort Duquesne, and from then on to the close of the war he served continuously, his last campaign being with Col. Henry Bouquet on the western frontier.
From 1765 until 1779 he was a local magistrate in Lancaster County and was engaged in the iron industryof that place. On the outbreak of the Revolution, without waiting for a commission, he raised a company of militia on his own responsibility. The Continental Congress appointed him colonel of the 16th Pennsylvania Battalion on January 22, 1776.
By that time his regiment was already on its way to join General Benedict Arnold on his ill-fated Canadian expedition. He joined his regiment and rendered valuable service, saving Arnold from possible capture by the British commander Forster at Lachine, by arriving with four companies and forcing Forster to retire to Fort Allen, at the head of Montreal Island.
During June 1776 Arnold kept De Haas's detachment "dancing between Sorel and Montreal, " and soon thereafter the invading army, defeated and thinned by desertion, fell back on Fort Ticonderoga. The troops of the 16th Pennsylvania Battalion reached their homes in December, and afterward formed the nucleus for the 2nd Pennsylvania Regiment, Continental Line.
De Haas was commissioned brigadier-general of the Continental Line, February 21, 1777, but at the close of that year he suddenly resigned his commission and returned to Lancaster County. His resignation has never been fully explained. He seems to have been a strict disciplinarian and hence made enemies in the service; but Washington believed him to be a capable officer and regretted his loss.
In 1778 De Haas offered his services to the board of war to lead an expedition against the Indians who had raided the Wyoming Valley. He collected some local militia and marched to the scene, but General Arnold sent Colonel Hartley with a detachment of regular troops and orders to take command. The next year De Haas moved to Philadelphia where he remained until his death.
De Haas was married to Eleanor Bingham.
