Simeon De Witt, who was born in the year of 1756, was the Geographer and Surveyor-General of the Continental Army during the American Revolution. De Witt had spent his childhood in Ulster County, in New York. He was one of the fourteen children of Jannetje Vernooy and father Dr. Andries De Witt, who was a physician.
In the class of 1776 at Queens College, presently known as Rutgers College of Rutgers University in New Brunswick, New Jersey, Simeon De Witt was the only graduate. In the year of 1778, De Witt was chosen as assistant to the Geographer and Surveyor of the Army Colonel Robert Erskine and had enriched a number of important maps of the history. Thus he became one of the well-known Map Makers of Modern Era. After the death of Erskine, De Witt got the name of "Geographer and Surveyor of the Army" in December 1780.
Simeon De Witt became the "Surveyor General of New York State" after the war. He was also the Surveyor General of the State of New York for a period of fifty years from 1784 until his death. Great number of Works of Simeon De Witt were produced after this till his death in 1834.