1755) shortly after the conclusion of the Revolutionary War, William A.G. Dade could trace his descent to a 17th century English Royalist Francis Dade who emigrated to Virginia and became Speaker of the House of Burgesses, as well as major of the Westmoreland County militia before the creation of most of the counties where this man would hold judicial responsibilities.
William A.G. Dade received a private education appropriate to his class, and read law with a local lawyer.
[5] Prince William County voters elected Dade as one of the men representing them in the Virginia House of Delegates in 1807, and he was succeeded by his investor partner John Howe Peyton, who had a much longer political career, albeit mostly after moving to Augusta County, Virginia.
Interested in promoting education, and as a father with children, Dade served as trustee for the new academy established in Dumfries before the town's decline.
In 1818 the General Assembly appointed Dade as one of the six men authorized to determine the location of the University of Virginia.
When the Virginia General Assembly decided to call a convention to revise the state constitution, Dade received the most votes among candidate in the large district approximating that for his judicial duties.
The eldest son, Charles Edward Dade, inherited the main plantation (by the terms of his will rather than primogeniture which had been abolished.