Parthia became independent from the Seleucid Empire in the 3rd century BCE and was ruled by Arsaces, who started the Arsacid dynasty. By 141 BCE, Mithradates I controlled most of Iran and Mesopotamia, leading to the growth of the Parthian Empire as a major power between Rome and the borders of India and China. The empire was eventually taken over by Ardashir in the 3rd century CE, leading to the establishment of the Sasanian Empire.