East Tennessee is part of Appalachia. At the end of the French and Indian War, colonists began drifting into the area. In 1769, they first settled along the Watauga River. During the Revolution, the Overmountain Men defeated British loyalists at the Battle of Kings Mountain. The State of Franklin was formed in the 1780s, but never admitted to the Union.
...one half of the plantation and survey aforesaid one half of the town lot, waggon, farming utensils and Joiners tools to be at his disposal at the time and manner aforesaid, together with one half of the balance of all my moveable estate at his mother's death or second marriage making him an equal sharer in all respects with his brother John.
Sullivan County is in far northeast corner of Tennessee between North Carolina and Virginia and was originally part of those states. It was formed in 1779 when it was divided from Washington County.