Demetrius III Eucaerus

Demetrius III Theos Philopator Soter Philometor Euergetes Callinicus (Ancient Greek: Δημήτριος θεός Φιλοπάτωρ σωτήρ Φιλομήτωρ Εὐεργέτης Καλλίνικος, surnamed Eucaerus; between 124 and 109 BC – after 87 BC) was a Seleucid monarch who reigned as the King of Syria between 96 and 87 BC. He was a son of Antiochus VIII and, most likely, his Egyptian wife Tryphaena. Demetrius III's early life was spent in a period of civil war between his father and his uncle Antiochus IX, which ended with the assassination of Antiochus VIII in 96 BC. After the death of their father, Demetrius III took control of Damascus while his brother Seleucus VI prepared for war against Antiochus IX, who occupied the Syrian capital Antioch.

The civil war dragged on; Seleucus VI eliminated his uncle, whose heir Antiochus X counterattacked and drove Seleucus VI to his death. Then the twins Antiochus XI and Philip I, brothers of Demetrius III, attempted to avenge Seleucus VI; it ended with the death of Antiochus XI and the interference of Demetrius III on the side of Philip I in a war against Antiochus X that probably lasted until 88 BC. In 89 BC, Demetrius III invaded Judaea and crushed the forces of its king, Alexander Jannaeus; his near victory was cut short by the death of Antiochus X. Demetrius III rushed to Antioch before Philip I could take advantage of the power vacuum and strengthen his position relative to Demetrius III.