Parthia (Old Persian: 𐎱𐎼𐎰𐎺 Parθava; Parthian: 𐭐𐭓𐭕𐭅 Parθaw; Middle Persian: 𐭯𐭫𐭮𐭥𐭡𐭥 Pahlaw) 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 (247 BC – 224 AD). 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.
Parthians in the context of Seleucid era
The Seleucid era ("SE") or Anno Graecorum (literally "year of the Greeks" or "Greek year"), sometimes denoted "AG," was a system of numbering years in use by the Seleucid Empire and other countries among the ancient Hellenistic civilizations, and later by the Parthians. It is sometimes referred to as "the dominion of the Seleucidæ," or the Year of Alexander. The era dates from Seleucus I Nicator's reconquest of Babylon in 312/11 BC after his exile in Ptolemaic Egypt, considered by Seleucus and his court to mark the founding of the Seleucid Empire. According to Jewish tradition, it was during the sixth year of Alexander the Great's reign (lege: possibly Alexander the Great's infant son, Alexander IV of Macedon) that they began to make use of this counting.
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