Moses Warren, Jr., was born September 5, 1762, in Fairfield, Connecticut, the son of Moses Warren and Judith Bailey. Like his father, who was captain of the second alarm company of Lyme in 1777, the younger Warren fought in the Revolutionary War. On January 18, 1784, he married Mehitabel Raymond (b. 1763) and they settled in Lyme, Connecticut. Warren began working as a surveyor and mapmaker, and in 1796 was made deputy land surveyor of Connecticut. In 1796-1797, he surveyed modern-day Ohio with the Connecticut Land Company, and assisted General Moses Cleveland in laying out the city of Cleveland, Ohio. Thereafter, he and his wife settled in New London, Connecticut, and Warren continued his cartographical work, and published several influential maps with George Gillet. Warren died in 1835.
In order to terminate land claims of Connecticut based upon its colonial charter, Congress in 1786 granted the state a sizeable territory along Lake Erie, just west of Pennsylvania, which became known as the Western Reserve. General Anthony Wayne's successful campaign against the Indians in 1794 made settlement feasible, and in 1796 the state sold the vast portion east of the Cuyahoga River to the Connecticut Land Company.