Byzantine units of measurement were a combination and modification of the ancient Greek and Roman units of measurement used in the Byzantine Empire. Until the reign of Justinian I (527–565), no universal system of units of measurement existed in the Byzantine world, and each region used its traditional measures. Justinian began the process of standardization that resulted in a specifically Byzantine system, chiefly due to the need of such a system for the fiscal administration. Official measurement and weighing was performed subject to an array of charges including the mestikon, miniatikon, zygastikon, kambaniatikon, gomariatikon, and samariatikon. Despite the central government's insistence on the use of official measures, other systems continued to be used in parallel, whether due to loc