Moses Chaplin was born about in 1717 Prince George's County Maryland. He was the son of William Chapline III (1686-1752) and Elizabeth Riley (1685-1745).
He lived in the part of Frederick County, Maryland that is now Washington County.
In 1740 Moses married Janette Caton.
He died on August 13, , 1762 in Keedysville Washington County, Maryland.