Lucius Aelius Megas Abgar IX was a Syriac ruler of Osroene from AD 177 to 212.
Andrew Louth in his "Who's Who in Eusebius" at the end of G. A. Williamson's translation of Eusebius of Caesarea's Ecclesiastical History gives the dates of Abgar's reign as from 179-214.
During the reign of Abgar the Great, Christians were favored in the realm of Osroene. It is thought by some that this led to the story of the letters between Abgar V and Jesus of Nazareth. In 1904, Adolf von Harnack proposed that Abgar IX may have been the origin of the story in Liber Pontificalis that King Lucius of Britain wrote to Pope Eleuterus. This theory, adopted by many modern scholars has been significantly challenged by David J. Knight
References
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