World Order in Late Antiquity: The 'Two Eyes' Rivalry of Byzantium and Sasanian Persia

The East Romans of Byzantium and the Sasanian Persians competed as geopolitical rivals for over four centuries between 224 to 628 AD. Through a series of intractable conflicts these two great empires would develop a dual hierarchy that sought to divide the known world between them. Despite competing claims to universal rule, mutual spheres of interest arose as both empires sought to create rules, norms, and standard practices of diplomatic behaviour to regulate their inter-imperial rivalry....