GREGORAS, NICEPHORUS (c. Byzantine historian, man of learning and religious controversialist, was brought up at Heraclea in Pontus. At an early age he settled at Constantinople, where he won the favour of Andronicus II. In 1326 Gregoras proposed (in a still extant treatise) certain reforms in the calendar, very similar to those introduced by Gregory XIII. in 1582. When Andronicus was dethroned (1328) by his grand son Andronicus III., Gregoras retired into private life. But after the death of the elder Andronicus, Gregoras won the favour of his grandson and was appointed to conduct the negotiations (for a union of the Greek and Latin churches) with the ambassadors of Pope John XXII. . Gregoras was then famous as a teacher, but was ruined by his opposition to Palamas in the Hesychast con troversy. After the doctrines of Palamas had been recognized at the synod of 1351, Gregoras, who refused to acquiesce, was prac tically imprisoned in a monastery for two years. Nothing is known of the end of his life. His chief work is his Roman History, in 37 books, of the years 1204 to 1359, which supplements and con tinues the work of George Pachymeres. This work and that of John Cantacuzene supplement and correct each other and should be read together. The other writings of Gregoras, which (with a few exceptions) still remain unpublished, attest his great versa tility. Amongst them may be mentioned a history of the dispute with Palamas; biographies of his uncle and early instructor John, metropolitan of Heraclea, and of the martyr Codratus of Antioch; funeral orations for Theodore Metochita and the two emperors Andronicus; commentaries on the wanderings of Odysseus and on Synesius's treatise on dreams ; tracts on orthography and on words of doubtful meaning; a philosophical dialogue called Flor entius; or, Concerning Wisdom; astronomical treatises on the date of Easter and the preparation of the astrolabe; and an extensive correspondence.