He was born into a once influential family of Antioch which had recently lost most of its wealth and influence as a result of participation in Eugenius' revolt against emperor Diocletian. When 14 years old, Libanius fell in love with rhetoric and focused his whole life on it. He studied in Athens and began his career in Constantinople, but was soon exiled to Nicomedia.
In 354, he accepted the chair of rhetoric in Antioch, where he stayed until his death. Although a pagan, his students included the Christians John Chrysostom and Theodore of Mopsuestia. He was a friend of the pagan emperor Julian (362-363), but was rewarded with an honorary praetorian prefect by the very Christian emperor Theodosius I (379-393).