 William Stacy was born in Gloucester, Massachusetts in 1734 and died in Marietta, Ohio in 1802. Slightly different years of birth and death have been reported. Stacy grew up in Gloucester on the coast of Massachusetts and worked as a shoemaker, a trade learned from his father; he may also have worked in the seafaring business. William Stacy married Sarah Day in 1754. Subsequently, during 1757, they moved away from the coast to New Salem in western Massachusetts, and raised a large family. Stacy took up farming and continued his work as a shoemaker. He also became a commercial banker, loaning money at interest before there were any banks in the area. His customers were from New Salem and other towns in the Province of Massachusetts Bay. By the time of his early middle age, William Stacy was living a comfortable life; he was successful and widely known. During 1775, at the age of 41, William Stacy's life changed with the onset of friction between the Thirteen Colonies and the British Empire.
