Persia
Before the Parths occupied what is now Iran the Persians lived there. Kings of that time are called the Achaemenids. They fought famous wars with Athens etc., but they are only mentioned here if they are referred to in documents dealing mainly with Roman history.
This includes:
Cyrus, Darius, Xerxes

Parthia: the Arsacids
Alexander the Great destroyed the Persian empire and its people became a part of the Seleucid kingdom. In 247/48 BC the Arsacids revolted and created a Parthian kingdom. Kings were:
171-138 BC:Mithradates I
123- 88 BCMithradates II
58 - 55 BC: Mithradates III
56 - 38 BC:Orodes II
Defeated Crassus at Carrhae, but in 38 BC Marc Antony and Ventidius Bassus dispossesed him
40 - 38 BC: Pacorus invaded Syria and Palestina
Artabanus II
105-147 AD:Vologases II
109-147 AD:Osroes
128-147 AD:Mithradates IV
213-215 AD:Caracalla fights against Artabanus V and Vologaeses VI

Parthia: the Sassanids
In 224 the Sassanids revolted and became kings. They fought constantly against Rome.
Kings were:
241-272: Sapor I, who in 257 captured Valentian
Bharam I
Maximianus fought with Narses
310-379: Sapor II
383-388: Sapor III
Nohodares

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