Dionysus Exiguus

St. Dionysius Exiguus (Dionysius the Humble)
Born	c. 470 Scythia Minor, Eastern Roman Empire
Died	c. 544 (aged 73 or 74) Rome, Kingdom of the Ostrogoths
Venerated in	Eastern Orthodox Church
Canonized	8 July 2008, Bucharest by the Synod of the Romanian Orthodox Church
Feast	1 September (first day of the Byzantine liturgical year)

Dionysius Exiguus (Latin for "Dionysius the Humble"; c. AD 470 – c. AD 544) was a 6th-century monk born in Scythia Minor (probably modern Dobruja, in Romania and Bulgaria). He was a member of a community of Scythian monks concentrated in Tomis, the major city of Scythia Minor. Dionysius is best known as the inventor of the Anno Domini (AD) era, which is used to number the years of both the Gregorian calendar and the (Christianised) Julian calendar. Some churches adopted his computus (calculation) for the dates of Easter.

From about 500 he lived in Rome, where, as a learned member of the Roman Curia, he translated from Greek into Latin 401 ecclesiastical canons, including the apostolical canons; the decrees of the councils of Nicaea, Constantinople, Chalcedon and Sardis; and a collection of the decretals of the popes from Siricius to Anastasius II. These Collectiones canonum Dionysianae had great authority in the West, and continues to guide church administrations. Dionysius also wrote a treatise on elementary mathematics.

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