Theodoret of Cyrus (c. AD 393 – c. 458/466) was born in Antioch. In his 20s he became a monk in the monastery of Nicerte not far from Apamea (wikipedia). In 423 CE, he was appointed Bishop of Cyrrhus, located about 80 Roman miles east of Antioch. Theodoret, who spoke Greek and Syriac but was unfamiliar with Latin and Hebrew, wrote a number of works including Ecclesiastical History which covered Church history from the rise of Arianism (late 3rd century CE?) until 429 CE (wikipedia). It was completed in 449-450 CE (wikipedia).