Antiochus III Epiphanes (Greek: Ἀντίοχος ὀ Ἐπιφανής, flourished 1st century BC and 1st century AD) was the ruler of the Kingdom of Commagene from 12 BC to 17 AD. He was the son and successor of King Mithridates III of Commagene and Princess of Media and Queen of Commagene, Iotapa, and of mixed Armenian, Greek and Median descent. His parents were first cousins.
When Antiochus died in 17 AD, his death created major issues for the kingdom. At the time of Antiochus’ death, Commagene was in political turmoil. The reasons for this situation are unclear, but it may have been the consequence of his children by his sister-wife Queen Iotapa, Antiochus and Iotapa being too young to succeed their father. This may have meant that there was no effective authority to prevent civil unrest and unite the citizens of Commagene.
Very little is known on his life and his reign as King. After Antiochus' death, two factions appeared. One faction was led by noblemen who wanted Commagene to be placed under the rule of the Roman Empire and the other faction was led by citizens who wanted Commagene's independence to be retained under the rule of their own king.
Both political factions sent embassies to Rome, seeking the advice and assistance of the Roman Emperor Tiberius to decide the future of Commagene. Tiberius decided to make Commagene a part of the Roman province of Syria. That decision was welcomed by many of the citizens by Commagene. Commagene remained under Roman rule until Roman Emperor Caligula restored the kingdom to Antiochus’ children in 38 AD.
Antiochus III and his son are honoured on the Philopappos Monument in Athens, Greece, dedicated to his great-grandson prince Gaius Julius Antiochus Epiphanes Philopappos, who was a prominent and respected citizen in Athens. In the left figure of the monument is a statue of Antiochus III's son, Antiochus IV. Below Antiochus IV is an inscription that states King Antiochus son of King Antiochus.