In June 218, Macrinus was defeated by the forces supporting Elagabalus outside Antioch, while Artabanus faced the uprising of the Persian Sassanid clan under Ardashir I. Nisibis was thus the last major battle between Rome and Parthia, as the Parthian dynasty was a few years later overthrown by Ardashir. However, warfare between Rome and Persia soon resumed, as Ardashir and Macrinus' successor Alexander Severus fought over Mesopotamia, and hostilities continued intermittently until the Muslim conquests.