||This article includes a list of references, but its sources remain unclear because it has insufficient inline citations. (May 2010)|
|United States Senator
March 4, 1789 – March 12, 1790
|Succeeded by||John Walker|
Prince William County, Virginia
|Died||March 12, 1790 (aged 49–50)
Grayson was born in 1740 to parents Benjamin Grayson and Susannah Monroe Grayson at Belle Aire Plantation  in what is now Woodbridge, Virginia. He attended the University of Pennsylvania, graduating in 1760. He attended university in Great Britain, but it is uncertain whether he attended Oxford University or the University of Edinburgh. He practiced law in Dumfries, Virginia, until the American Revolutionary War began.
Serving as an aide-de-camp to George Washington, Grayson rose to the rank of lieutenant colonel. In 1777, he recruited a regiment for the Continental Army known as Grayson's Regiment, and served as its colonel through the Philadelphia campaign. In 1778, he served on a commission dealing with war prisoners, and in 1779 he resigned his military commission to serve on the Congressional Board of War. In 1781 he returned to Dumfries to practice law. Like many Continental Army officers, he was an original member of the Society of the Cincinnati.
Grayson was a delegate to the Confederation Congress from 1785 to 1787. As an Anti-Federalist (one of the men who in Virginia called themselves "Republicans"), he joined George Mason, James Monroe, and Patrick Henry in opposing ratification of the United States Constitution at the Virginia Ratification Convention in 1788. In that Convention, Grayson argued that the proposed constitution was neither fish nor fowl—neither strong enough for a national government nor decentralized enough for a federal one — and thus eventually would either degenerate into a despotism or result in the dissolution of the Union. Although the Anti-Federalists lost that battle, Patrick Henry, Virginia's leading Anti-Federalist, rewarded Grayson by arranging his election to the first United States Senate. Grayson served from March 4, 1789 until his death on March 12, 1790. He and Richard Henry Lee were the only members of the first Senate who had opposed ratification, and so they were unhappy (but not surprised) when the Bill of Rights omitted any provisions making serious corrections to the division of powers between the central government and the states. Grayson continued to believe that the Philadelphia Convention had struck precisely the wrong balance.
|“||The Ancients were surely men of more candor than We are; they contended openly for an abolition of debts in so many Words, while we strive as hard for the same thing under the decent and specious pretense of a circulating medium. Montesquieu was not wrong when he said the democratical might be as tyrannical as the despotic, for where is there greater act of despotism than that of issuing paper to depreciate for the paying debts, on easy terms.||”|
His brother was Reverend Spence Monroe Grayson of Pohick Church, and through his mother he was a cousin to James Monroe. His wife was Eleanor Smallwood, a sister of Maryland Governor William Smallwood. Grayson was the grandfather of William Grayson Carter, a Kentucky state senator, and Confederate General John Breckinridge Grayson.
Grayson is interred in the Grayson family vault at Belle Aire. The vault was encased in concrete  and buried by the Daughters of the American Revolution in the early 20th century. It is currently located on private property.
- McCarthy, Daniel (2010-03-04) A Weekend With Douglass Adair, The American Conservative
Further reading 
- K[evin]. R. Constantine Gutzman. "Grayson, William". American National Biography Online, February 2000.
- Kevin R. C. Gutzman, Virginia's American Revolution: From Dominion to Republic, 1776-1840 (Lexington Books, 2007).
- William Grayson at the Biographical Directory of the United States Congress
- "The Continental Army Bibliography: Additional Regiments". United States Army Center of Military History. - bibliography for Grayson's Regiment in the Continental Army
- William Grayson by Margaret L. Edwards
- The Graysons of Belle Aire in Prince William County and Georgia
- William Grayson's Grave at the Historical Marker Database
- The Grayson Memorial Bandstand
- The Grayson Family a personal genealogy page
|United States Senate|
|United States Senator (Class 1) from Virginia
March 4, 1789 – March 12, 1790
Served alongside: Richard H. Lee