William Gray (June 27, 1750 (old style; July 8, 1750 new style)– November 4, 1825) was a Massachusetts merchant and politician. Born into a lower-class family in Lynn, Massachusetts, he managed to build his own business and rise through the state's political ranks, becoming the richest man in New England, and in the eyes of many the richest man in all of America. Prior to the War of 1812, William Gray had the largest private fleet in the United States with 60 square-rigged vessels.^[1]

Gray first served as a state senator, before becoming the ninth lieutenant governor of Massachusetts, serving from 1810 to 1812. He married Elizabeth Chipman (May, 1756 - September 24, 1823) in 1782. Elizabeth was a pioneer in philanthropy, volunteering a significant portion of her time to helping the poorest citizens of Boston.

In 1820, he was elected a member of the American Antiquarian Society^[2]

He owned Gray's Wharf in Charlestown.^[3] In Boston "he lived on Summer Street, in the mansion previously occupied by Governor Sullivan."^[4] For a time, Nathaniel Prime served as his coachman.^[5]

Elizabeth and William had five sons and one daughter:

• William Rufus Gray (1783-1831), a merchant.
• Henry Gray, a merchant. (1784-1854)
• Lucia Gray Swett (1788-1844)
• Francis Calley Gray (1790–1856), a politician, writer, orator, art collector.
• John Chipman Gray, (1793-1881) a politician
• Horace (1801–1873), father of Supreme Court of the United States associate justice, Horace Gray, and of Harvard Law School professor, John Chipman Gray