By the end of the Revolution, Martin's place as chief colonial Indian agent seemed secure. In January 1780, Virginia governor Thomas Jefferson directed Martin to negotiate with the Cherokees to secure land around a new fort being overseen by General George Rogers Clark at the mouth of the Ohio River (Fort Jefferson). In the fall of 1783, the State of Virginia built a new fort at the Cumberland Gap, replacing an older fort which was adjudged to lie within the boundaries of North Carolina. The new Virginia fort was designed as the primary residence for Martin while he was in the region on official business. And in 1784, Thomas Jefferson directed Martin to use his connections with the Cherokees to negotiate for more land between the Carolinas and the Mississippi to establish American sovereignty over the region.