George Mason IV (December 11, 1725 – October 7, 1792) was an American patriot, statesman, and delegate from Virginia to the U.S. Constitutional Convention. Along with James Madison, he is called the "Father of the Bill of Rights." For these reasons he is considered one of the "Founding Fathers" of the United States.

Like anti-federalist Patrick Henry, Mason was a leader of those who pressed for the addition of explicitly stated individual rights to the U.S. Constitution, and did not sign the document in part because it lacked such a statement. His efforts eventually succeeded in convincing the Federalists to add the first ten amendments of the Constitution. These amendments, collectively known as the Bill of Rights, were based on the earlier Virginia Declaration of Rights, which Mason had drafted in 1776.

On the nagging issue of slavery, Mason walked a fine line. Although a slaveholder himself, he found slavery repugnant for a variety of reasons. He wanted to ban further importation of slaves from Africa and prevent slavery from spreading to more states. However, he did not want the new federal government to be able to ban slavery where it already existed, because he anticipated that such an act would be difficult and controversial.

Family

George Mason was born on December 11,1725 to George and Ann Thomson Mason at the Mason family plantation in Fairfax County, Virginia. His father died in 1735 in a boating accident on the Potomac, when the boat capsized and he drowned. After this event the younger Mason lived with his uncle John Mercer. On April 4, 1750, he married sixteen-year-old Ann Eilbeck, from a plantation in Charles County, Maryland. They lived in a house on his property in Dogue's Neck, Virginia. Mason completed construction of Gunston Hall, a plantation house on the Potomac River, in 1759. He and his wife had twelve children, nine of whom survived to adulthood. Mason's first child, George Mason V of Lexington , was born on April 30, 1753. He married Elizabeth Mary Ann Barnes Hooe (Betsy) on April 22, 1784, and after having six children, died on December 5, 1796. The next Mason offspring was Ann Eilbeck Mason, fondly known as Nancy. Born on January 13, 1755, she married Rinaldo Johnson on February 4, 1789 and had three children before dying in 1814. The third child was named William Mason, but he did not live over a year and died in 1757. The fourth child, born on October 22, 1757, was also named William Mason, and he married Ann Stuart on July 11, 1793. They had five children together, and he died in 1818. The fifth child was a son they named Thomson Mason. He was born on March 4, 1759 and died on March 11, 1820. Thomson married Sarah McCarty Chichester of Newington in 1784; they had eight children.

George Mason's sixth child, christened Sarah Eilbeck Mason but fondly known as Sally, was born on December 11, 1760 and married in 1778. She had ten children with her husband Daniel McCarty, Jr. before dying on September 11, 1823. The seventh of the Mason children was another girl, Mary Thomson Mason. She was born on January 24, 1764, and married John Travers Cooke on November 18, 1784, with whom she had ten children before dying in 1806. John Mason was Mason's eighth child, being born on April 4, 1766. He married Anna Marie Murray on February 14, 1796, had ten children, and died on March 19, 1849. The ninth child was a daughter named Elizabeth Mason. She was born on April 19, 1768 and died sometime between 1792 and June of 1797. She married William Thornton in 1789 and they had two children. The tenth child, Thomas Mason, was born on May 1, 1770 and died on September 18, 1800. He married Sarah Barnes Hooe on April 22, 1793 and the two had four children together.