Brent was born in Stafford County on July 26, 1733, the son of William Brent and Jane Brent. In about 1754, he married Eleanor Carroll, of Maryland, whose brother John Carroll became the first Catholic bishop in the United States. Brent and his wife descended from noted Catholic families, but he converted to the Church of England, and they both attended services at Overwharton Parish. Two of their three sons and their four daughters found spouses among the prominent Virginia and Maryland families of Ambler, Carroll, Hill, Lee, and Sewall. Richard Brent, their middle son, served in the House of Representatives and the United States Senate.
Brent inherited several thousand acres in King George, Prince William, Stafford, and Westmoreland counties, as well as in Maryland and points west. He raced and bred a noted stable of thoroughbred horses. An astute businessman, Brent earned large stud fees for his stallions Figure and Republican and owned Ebony, a famous brood mare. When advertising the stud services of Don Carlos in 1777, he offered to accept either money or young enslaved workers in payment.
In May 1757, Brent became a justice of the peace in Stafford County. He joined the other justices in resigning to protest the Stamp Act in October 1765, but the resignation was ignored, and he continued as a justice until his death. Brent signed the Westmoreland Association in February 1766, also in protest of the Stamp Act, and in 1774, he was elected to the Stafford County Committee to enforce the nonimportation associations enacted by the Virginia Revolutionary Conventions and the Continental Congress. On April 8, 1776, he was elected one of two delegates from Stafford County to the Fifth Revolutionary Convention. Brent served on the Committee on Privileges and Elections and voted for independence, for the Virginia Declaration of Rights, and for the first constitution of the commonwealth.
On July 23, 1776, a raiding party from HMS Roebuck landed in Stafford County and destroyed a number of buildings, including Brent’s elegant brick mansion called Richland at the mouth of Aquia Creek. Brent rebuilt his house and remained in public life. He represented Stafford County in the House of Delegates in the autumn of 1776, when he served on the Committee on Privileges and Elections, and again in 1778, when he sat on the Committee on Propositions and Grievances. Brent was elected to the Senate of Virginia in the spring of 1780 to represent the district consisting of King George, Stafford, and Westmoreland counties. He wrote his will on January 7, 1782, and added a codicil on the next day and a second codicil on January 9. William Brent died between that date and the April 1782 meeting of the Stafford County Court at which his will was proved. The court should have met on April 8, but its sessions could have been prolonged for several days. Brent was buried in the family vault at his estate.
