Parthia is a historical region located in northeastern Greater Iran. It was conquered and subjugated by the empire of the Medes during the 7th century BC, was incorporated into the subsequent Achaemenid Empire under Cyrus the Great in the 6th century BC, and formed part of the Hellenistic Seleucid Empire after the 4th-century BC conquests of Alexander the Great. The region later served as the political and cultural base of the Eastern Iranian Parni people and Arsacid dynasty, rulers of the Parthian Empire. The Sasanian Empire, the last state of pre-Islamic Iran, also held the region and maintained the seven Parthian clans as part of their feudal aristocracy.

पार्थ या पार्थिया उत्तर-पूर्वी ईरान और उस के समीप के क्षेत्र का ऐतिहासिक नाम है। यहाँ कभी पार्थी लोग अपना साम्राज्य चलाया करते थे जो २४७ ईसापूर्व से २२४ ईसवी तक चला। इस साम्राज्य को अशकानी साम्राज्य के नाम से भी जाना जाता है। पार्थी लोग एक ईरानी भाषा बोलने वाली जाति थी।