Final answer:
The backcountry was located west of the Appalachian Mountains, in the area sought after by colonists for settlement post-Seven Years' War, but was restricted by the British Proclamation of 1763.
Step-by-step explanation:
The backcountry in colonial days was located west of the Appalachian Mountains, near what would be today the eastern United States. After the British victory in the Seven Years' War, colonists were eager to move westward, away from the increasingly crowded coastal regions, in pursuit of the fertile lands of the Ohio Valley. The British government's Proclamation Line of 1763, however, prohibited colonists from settling these lands, creating significant tension and contributing to the dissatisfaction that would culminate in the American Revolution.