Pacorus I (also spelled Pakoros I; ; died 38 BC) was a Parthian prince, who was the son and heir of Orodes II (). The numismatist David Sellwood deduced that Pacorus ruled in . It is uncertain whether Pacorus ruled alongside his father, or ruled independently. His wife was an unnamed Armenian princess, who was a sister of the Artaxiad king of Armenia, Artavasdes II (). Following the Parthian victory against the Romans at the Battle of Carrhae in 53 BC, the Parthians attempted to capture Roman-held territories in Western Asia, with Pacorus acting as one of the leading commanders. Although they were initially successful, they were repelled by the Romans. Pacorus himself was defeated and killed at the Battle of Mount Gindarus by the forces of the Publius Ventidius Bassus. His death spurred a succession crisis in which Orodes II, deeply afflicted by the death of his favourite son, relinquished the throne to his other son Phraates IV () as his new heir. Name The name is the Latin form of the Greek Pakoros (), itself a variant of the Middle Iranian Pakur, derived from Old Iranian bag-puhr ('son of a god'). The Armenian and Georgian transliteration is Bakur (respectively; Բակուր, ბაკური). Biography Pacorus was the eldest son and heir of Orodes II (), the ruler of the Parthian Empire. His mother may have been a princess from the peripheries of eastern Parthia. Shortly before the Battle of Carrhae (modern Harran, southeastern Turkey) ensued between the Parthians and a Roman army, commanded by the triumvir, Marcus Licinius Crassus, Orodes II invaded Armenia, cutting off Crassus's support from his ally, the Artaxiad king Artavasdes II (). Orodes II persuaded Artavasdes to a marriage alliance between Pacorus and Artavasdes's sister. Following Crassus's defeat and death at Carrhae, the Parthians attempted to capture Roman-held territories in Western Asia. Pacorus and his commander Osaces raided Syria, going as far as Antioch in 51 BC, but were repulsed by Gaius Cassius Longinus, who ambushed and killed Osaces. Orodes II sided with Pompey in the civil war against Julius Caesar and even sent troops to support the anti-Caesarian forces at the Battle of Philippi in 42 BC. Quintus Labienus, a general loyal to Cassius and Brutus, sided with Parthia against the Second Triumvirate in 40 BC; the following year he invaded Syria alongside Pacorus. The triumvir Mark Antony was unable to lead the Roman defense