The development of the mayflower compact(first official document that mentions communal governing), the failure of Britain to maintain salutary neglect, the taxation without representation imposed on America by Britain, and Benjamin franklin who spoke of the unification of the New England colonies.
The delegates met so they could discuss the issues with the continuous war of 1812.
C. Buffer zone between Carolina and Spanish Florida
I think it was the Armory Show in New York. That's what I know. Hope this helps :)