In the history of international law and relations, 'Westphalian system' is commonly used as shorthand to describe the 'modern' paradigm of international relations based on a system of exclusive authority vested in sovereign State actors, and evidenced in the Peace of Westphalia in 1648. The discussion here probes the way in which such ideas about governance took root and consolidated into a consensus amoung political leaders across seventeenth century Europe. What were the means of intellectual exchange and political discourse which facilitated the Westphalian sea-change? This study considers some media which may have been exploited in a significant way in early modern European society for the dissemination of argument and ideas about governance. Two major forms are of particular interest in this context: visual art, with its rich iconographical content; and various kinds of dramatic presentation capable of communicating with both elite and popular audiences.