Cabell was the son of William Cabell (1700–1774), a prominent physician, and his first wife, Elizabeth Burks Cabell. He must have been conceived either before his father’s departure for England in 1735 or after his return in 1741. Little is known about Cabell’s early years or his studies, although his parents probably ensured that he was well educated, as were all their other children. His brothers included Joseph Cabell, who served in the General Assembly, and William Cabell (1730–1798), who served in the Fifth Virginia Revolutionary Convention and the 1788 Virginia Ratifying Convention. On May 20, 1762, Cabell married Paulina Jordon. They had seven sons and three daughters, but three sons died before reaching adulthood. Cabell’s wife died on July 31, 1781, and on July 19, 1787, he married Elizabeth Brierton Jones. They had no children. When Cabell drew up his will shortly before his death, he also provided for his two sons and one daughter by Frances Johnson.
Cabell acquired large tracts of land in Buckingham County, and at his death possessed more than 3,000 acres on which he raised tobacco and livestock, including horses and cattle. In October 1764, the General Assembly established a public ferry across the Fluvanna River (now the James River) connecting his estates. Cabell had become a captain in the Buckingham County militia by September 1763, and by 1767, he had been appointed a justice of the peace for the county. When Virginia’s counties formed committees in 1775 to enforce the economic measures adopted by the Continental Congress to pressure the British into repealing unpopular tax measures and then to organize for the defense of the colony, he was elected chairman of the Buckingham County Committee. The Virginia Committee of Safety appointed Cabell as county lieutenant, or commander of the Buckingham County militia, on September 26, 1775.
In April 1776, he was elected to the last of the Virginia Revolutionary Conventions and attended its sessions in Williamsburg from May 6 through July 5. There, Cabell served on the Committee of Propositions and Grievances. He and fellow Buckingham County delegate Charles Patteson received instructions from their constituents directing them to call for a complete break with England and to work for a constitution guaranteeing full representation and free elections. Even before these instructions reached Williamsburg, Cabell had voted on May 15, 1776, to instruct the Virginia delegates to Congress to introduce a resolution declaring the colonies independent. He was probably also present on June 12 and 29, 1776, when the convention unanimously adopted the Virginia Declaration of Rights and the first Constitution of Virginia.
Cabell represented Buckingham County in the House of Delegates in 1776 and again served on the Committee of Propositions and Grievances. He was reelected to one-year terms in 1777, 1780, and 1783, although he did not always attend. In the last session, he served on the Committee of Privileges and Elections. After the Revolutionary War, Cabell continued to manage his plantations and serve as a justice of the peace. In November 1788, the assembly appointed him a trustee for the town of Greensville in Buckingham County. John Cabell dated his will on April 22, 1815, and died sometime between then and June 12, 1815, when the will was proved in the Buckingham County Court.
