Contemporaneously with the fall and transformation of the Roman West, the Iranian Empire yielded its East to Hun—and later Turk—conquerors. This article traces the development of post-Iranian regimes through the dynamic interplay of nomadic and sedentary political institutions in the fourth through early seventh centuries. The conquerors adopted Iranian institutions, integrated the Iranian aristocracy, and presented themselves as the legitimate heirs of the kings of kings in a manner reminiscent of post-Roman rulers. At the same time, however, the Huns and the Turks retained the superior military resources of nomadic imperialism, included the Iranian East in trans-Eurasian networks, and distinguished themselves as ruling ethno-classes tied to the steppe. The resulting hybrid political culture came to be known as Turan.