The Parthian Wars
The initial conflict between the Parthians and Rome came as they divided the Seleucid empire. In 69 B.C., they concluded a treaty which set the border between the Parthian empire and Syria, a Roman province, at the Euphrates. They would hold what is currently western Iraq and eastern Iran.
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In 53 B.C., ambition and a desire for fame motivated Marcus Licinius, a member of the
First Triumvirate of Rome, to attempt to conquer Persia. Though Persia was divided along tribal loyalties, this outside attack solidified them. At Carchemish, Licinius attacked with tired troops against the advice of his generals and was defeated.
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Conflict between the followers of Julius Caesar and Pompey also brewed. With the death of Pompey, Roman influence in the eastern provinces waned. When civil war erupted upon the death of Caesar, the Parthians moved westward, taking Syria. With the help of a collaborator they also occupied Judea. Hyrcanus II was deposed as high priest and king of Judea and replaced by Antigonus, the last Hasmonaean ruler of Judea, who had assisted the Parthians.
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The Parthian rule over Judea and Syria would last from 40 to 37 B.C., when they were extracted from Judea and Syria. Warfare would continue to burst out between Rome and the Parthians for another century, but the Parthians would never move westward again.
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