The period that begun with the reign of Herakleios in 610 and ended with the accession of the Macedonian Emperors in 867, constitutes a transitional period for Byzantium. The two centuries after Justinian and especially the period 640-843 are known in art history as the Early Byzantine period, a term used to distinguish the end of the late Roman tradition from the beginning of a new era, dominated by an austerely structured, transcendental form of art. The dispute caused by the monoenergetic-monotheletic heresy as well as by the iconoclastic discord influenced art greatly and brought about much literary activity in connection with the spiritual world.