Libanius, born at Antioch (1) (ce 314), died there (c.393), was a pagan Greek rhetorician whose writings embodied many of the traditional ideals and aspirations of elite life in the eastern Roman Mediterranean at a time when some its basic patterns were facing profound transformation. He belonged to a wealthy Antiochene curial family (see decuriones), and after a careful education at home was sent to study in Athens (336–40). Thereafter he taught rhetoric successively at Constantinople (340/1–346) and at Nicomedia. Recalled to Constantinople by Constantius II, he was offered but declined a chair of rhetoric at Athens; in 354 he accepted a salaried chair of rhetoric in Antioch, where he passed the rest of his life. His pupils numbered many distinguished pagans and Christians alike: John Chrysostom and Theodore of Mopsuestia almost certainly, Basil and Gregory (2) of Nazianzus probably, and Ammianus Marcellinus possibly. So much of his writing survives because his Atticizing Greek (see asianism and atticism), the result of painstaking labour, was much esteemed as a model of style in Byzantine times.

In his later years Libanius became a literary figure of renown, corresponding with many prominent fellow intellectuals, including the pagan emperor Julian, for whom he had an unbounded admiration, and whose death was a bitter blow. Apart from this attachment to Julian, Libanius avoided specific political ties, but his position, pupils’ careers, and writings made him a prominent public figure, ready and willing to comment on important matters of his time. His surviving works include not only 51 school declamations, numerous model rhetorical exercises and minor rhetorical works composed in the course of his teaching, but also 64 surviving speeches dealing with public and municipal affairs as well as educational and cultural matters. Many are addressed to emperors or high government officials, with whom he intervenes on behalf of the curials of Antioch (e.g. after the riot of 382). Some were never actually delivered, but were sent to their addressees and published. Other speeches include his funeral oration on Julian (Or.17), his encomium of Antioch (Or.11), and the autobiography which he composed in 374 (Or. 1). There also survives a collection of 1,600 letters: many of them recommendations for his pupils or requests for favours. His general prominence, seemingly unaffected by his paganism (in which there is little sign of any Neoplatonism) was rewarded with the honorary title of praetorian prefect (see praefectus praetorio) granted him by the Christian Emperor Theodosius (2) I.

Through these works, composed over the entirety of his career, a strong sense emerges of the twin impacts upon older patterns of elite life of the rise of Christianity and the emergence of a properly imperial bureaucracy in the eastern Mediterranean focused on the new imperial Senate in Constantinople. The latter's career structures and patronage ties emerge clearly from his letters, while other works lament the new popularity of Latin, law, and even shorthand over traditional Greek rhetoric.