Phraates I

Phraates I of Parthia
Reign	168–165 BC
Predecessor	Phriapatius of Parthia
Successor	Mithridates I of Parthia
Born	Unknown
Died	165 BC
Dynasty	Arsacid dynasty
Religion	Zoroastrianism

Phraates I of Parthia, ruler of the Parthian Empire from ca. 168–165 BC. He subdued the Amardians (lat. Amardis), mountaineers occupying eastern portion of the Elburz range, south of the Caspian Sea. He died relatively young, and appointed as his successor not one of his sons, but his brother Mithridates I (165–132 BC).

The exact date of his ascension is the subject of some confusion. He may have succeeded his father Phriapatius (185–170 BC) on the throne. However, recent evidence from Nisa suggests that a great-grandson of Arsaces I reigned briefly after Priapatius' death in 170. In this reconstruction, this previously unknown "Arsaces IV" reigned ca. 170-168 BC and was then succeeded by Phraates I (which would make Phraates "Arsaces V").

At beginning of his reign Phraates I directed his arms towards territory inhabited by Amardians, a poor but warlike people, who appear to have occupied eastern portion of the Elburz range, south of the Caspian Sea, what is probably today immediately south of Māzandarān and Astarabad. The reduction of these fierce mountaineers is likely to have occupied him for some years, since their country was exceedingly strong and difficult.

At that time Amardi were de facto nominally subjects of the Seleucidae, we don't see any mention of assistance being rendered to them, nor even any complaint were being sent by Seleucus IV against unprovoked aggression of the Parthian monarch.

Account for inactivity of Seleucus IV Philopator in Syria, who was characterized as weak and pacific, might be consisted in part by war exhaustion of Syria in this period, which was consequence of his father's, Antiochus III, great war against Rome (192–188 BC) and heavy contribution which was imposed upon the Seleucids by the Treaty of Apamea. Syria might scarcely have recovered sufficient military strength to enter upon a new struggle, especially with a remote and powerful enemy. Seleucus IV also may have thought that material interests of Seleucid Empire were only minorly affected by Parthian aggression, since the Amardi were too poor to provide much tribute, so Syria considered their subjection rather a formality than a fact. Therefore, he allowed reduction of the Amardians, probably conceiving that their transfer under Arsacid dominance would neither increase Parthian power nor diminish his own.

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