Deiotarus

Deiotarus of Galatia (in Galatian and Greek Deiotaros, surnamed Philoromaios; c. 105 BC – 42 BC, 41 BC or 40 BC) was a Chief of the Tolistobogii in western Galatia, Asia Minor, and a King of Galatia ("Gallo-Graecia"). He was considered one of the most adept of Celtic kings, ruling the three tribes of Celtic Galatia from his fortress in Blucium.

The name Deiotarus is understood as *deiuo-taruos or "divine bull".

Deiotarus was a faithful ally of the Romans and became involved in the struggles between the Roman generals that led to the fall of the Republic from 44 BC. He changed sides and supported the triumvirs, keeping his kingdom until his death.

He is first heard of at the beginning of the Third Mithridatic War, when he drove out the troops of Mithridates VI of Pontus under Eumachus from Phrygia, and he was a witness where Mithridates VI saw his invasion of Phrygia stopped by the Roman ally, both in 75 BC or 74 BC. His most influential friend was Pompey, who, when settling the affairs of Asia after Mithridates VI failed in his invasion of Phrygia and was finally defeated by the Romans in 65 BC, 64 BC, 63 BC or 62 BC, rewarded him for his assistance against him with the title of King and an increase of territory (part of eastern Pontus, to which the Senate granted him Lesser Armenia and most of Galatia). On the outbreak of the civil war from 49 BC to 45 BC, Deiotarus naturally sided with his old patron and ally Pompey and the Optimates in their stand against Julius Caesar, who was defying the Senate, and after being defeated at the Battle of Pharsalus in 48 BC escaped with him to Asia. When Pompey was defeated he faced execution, but was saved in part due to the advocacy of Cicero between 49 BC and 45 BC. During this time, Pharnaces, the son of Mithridates, had seized Lesser Armenia, and defeated Deiotarus' army near Nicopolis. Fortunately for Deiotarus, Julius Caesar at that time (47 BC) arrived in Asia from Egypt, and was met by the tetrarch in the dress of a suppliant. Caesar pardoned him for having sided with Pompey, ordered him to resume his royal attire, and hastened against Pharnaces, whom he defeated at Zela.

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