Map of the states and territories of the United States as it was from September 1791 to March 1792. On September 9 1791, the District of Columbia was formed. On March 3 1792, the federal government sold the Erie Triangle to Pennsylvania.
{{Information| |Description=Map of the states and territories of the United States as it was from September 1791 to March 1792. On September 9 1791, the District of Columbia was formed. On March 3 1792, the federal government sold the Erie Triangle to Pen