What was the eastern border of the US after the Treaty of Paris?
I not 100% but I think it is Spain.
1783 was the date of the Treaty of Paris which officially separated the 13 American colonies from Great Britain. At that time the eastern border of what would be called the United States was delineated by the former colonies that had a coastline with the Atlantic Ocean. At that time all of the 13 colonies had a water access route to the Atlantic Ocean.