We had a varsity team, but we needed a plan.
Westphalia: Church Politics Adjusts Boundaries, Then Everything Changes
In 1648, the Treaty of Westphalia created the modern nation-state.
The Annapolis Convention had the original purpose of negotiating the joint ownership issues of the Potomac River between Virginia and Maryland. It seemed quite a natural thing to extend the discussion to other rivers which needed interstate cooperation, particularly the Susquehanna (Maryland and Pennsylvania) and Delaware (Pennsylvania, New Jersey, Delaware, and New York). That was at least six of the thirteen colonies, where Maryland and Virginia would find uniformity of rules to be advisable. It did not take too much imagination to suppose that the remaining states would wish to be involved, as well. It seems that much of the push for enlarging the local river discussion into a national discussion of broader issues came from Alexander Hamilton.