The making of the Constitution was an international event consisting of envoys from the thirteen states seeking to devise a solution to two diplomatic and security crises, that amongst the units (states and regions) of the Confederation with one another and with foreign powers. Early America is often structured as a fixed “nation” in studies of the period, but it is perhaps more accurate to classify it as comprising a state-system, one which was part of a larger international system. This article reviews how this dynamic and the role of diplomacy factored into constitutional reform in the 1780s by surveying the extant scholarship in the area and through analyzing debate at the Federal Convention and the reaction of the founders to the threat of internecine and foreign war during the Confederation. It concludes by discussing how its findings point to new lines of inquiry into the early American political experience.