Virginia convention
The Virginia Convention was the event in which representatives of Virginia debated and voted to support the new United States Constitution. James Madison was the chief among the delegates in favor of the new Constitution. Those opposed to the Constitution, including Patrick Henry, were concerned that a new federal government would have the potential to be too powerful. Eventually, in addition to ratifying the Constitution, they recommended a creation of a Bill of Rights, similar to Virginia's own Declaration of Rights.
This should not be confused with 5 previous Virginia Conventions, which acted as a sort of pseudo-government after the previous legislative body, the House of Burgesses, was disbanded.
Speech Relevance
As a matter of fact, the struggle we're in isn't new at all, no matter our confusion it's the same age-old struggle of mankind since his climb from the swamps. The struggle of those who believe that a few have the right to rule the many as against those who believe in individual liberty. James Madison speaking before the Virginia convention in 1788 said, "Since the general civilization of mankind, I believe there are more instances of the abridgement of the freedom of the people by gradual and silent encroachment of those in power, than by violent and sudden usurpation." Others, not realizing perhaps, that one day they would be serving the communist cause also subscribe to this belief and decided to use it.