Dionysius Exiguus

Byzantine monk, inventor of AD dating

Dionysius Exiguus (Latin for "Dionysius the Humble"; Greek: Διονύσιος; c. 470 – c. 544) was a 6th-century Eastern Roman monk born in Scythia Minor and active in Rome. He was a member of a community of Scythian monks concentrated in Tomis (modern Constanța, Romania), the major city of Scythia Minor. Dionysius is best known as the inventor of Anno Domini (AD) dating, which is used to number the years of both the Gregorian calendar and the (Christianised) Julian calendar.

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