Dionysius Exiguus was a 6th-century monk and scholar born in Scythia Minor who later lived and worked in Rome. A highly learned man proficient in both Greek and Latin, he served his religious community through extensive translation and legal work. He is most famous for developing the Anno Domini dating system to replace the era of the persecutor Diocletian. This chronological method, based on the incarnation of Christ, became a fundamental component of both the Julian and Gregorian calendars.