The Parthians (Arsacids)

c. 250 BC Diodotus, satrap of Bactria, achieves independence from Seleucid empire.
247 BC Arsaces, leaderof Parni, conquers the satrapy of Parthia
210 - 208 BC Campaigns of Antiochus III lead to temporary Greek recovery of Seleucid empire.
188 BC Antiochus defeated by Rome. Parthians recover lost territory, and expand south and west.
171 - 139 BC Mehrdad I conquers Mesopotamia amnd western Iran from the Seleucids.
139 - 123 BC Farhad II and Ardavan I consolidate Parthian rule in Mesopotamia and westen Iran. Both killed fighting the Saka in the north west.
124 - 87 BC Mehrdad II establishes Parthian empire as an unchallenged power. First Parthian interst in Armenia.
96 BC Meeting of Parthian Orobazus with Roman general Sulla.
69 66 BC Parthian treaties with Romans Lucullus and Pompey recognise Euphrates as a frontier.
53 BC Invasion of Parthia by Crassus ends in Roman disaster at Carrhae.
44 BC Assassination of Julius Caesar aborts his planned invasion of Parthia.
41 - 38 BC Victories by Roman Ventidius cancel Parthian gains in Syria ansd Anatolia.
36 BC Failure of Mark Antony's invasion of Parthia.
20 BC Peace between Roman emperor Augustus and Parthian king Farhad IV. Parthians return captured standards and prisoners. Armenia recognised as a Roman area.
AD 12 Parthians reject Roman educated king Vonones in favour of Ardavan II.
AD 38 - 45 Civil war in Parthia between Vardan and Godarz II.
AD 51 - 63 Under Valkash I tussle between Rome and Parthia over Armenia
AD 63 Treaty or Rhandeia between Rome and Parthia recognises Roman sovereigny but Parthian right to appoint the king.
AD 66 Tirdad crowned king of Armenia by Nero in Rome.
AD 72 - Alan invasion and civil war: Parthia in chaos.
AD 114 - 117 Roman emperor Trajan invades Parthia - capture of Ctesiphon. Armenia and Mesopotamia made provinces. Trajan dies.
AD 117 Hadrian gives up the new provinces, and Euphrates becomes the frontier once again.
AD 161 - 165 Valkash IV invades Armenia and Syria, but is driven back by Romans, who capture Ctesiphon again. Plague forces Romans to withdraw.
AD 195 Mesopotamia again a province under Septimius Severus.
AD 198 - Severus and Caracalla invade Parthia without success, but distraction enables growth of independent power in Persis. Sasanians Pabag and Ardashir expand rule into south west Iran.
AD 224 Defeat of Ardvan IV by Ardashir brings era of Parthian rule to an end. Beginning of Sasanian empire.