Cyril and Methodius were two Byzantine Christian theologians and Christian missionaries who were brothers. Through their work, they influenced the cultural development of all Slavs, for which they received the title "Apostles to the Slavs". The two brothers were born in Thessalonica, in present-day Greece – Cyril lived from 827-828 and Methodius 815-820. Cyril was born Constantine but took the name Cyril upon becoming a monk in Rome shortly before his death. The Glagolitic and Cyrillic alphabets are the oldest known Slavic alphabets, and were created by the two brothers and their students, to translate the Bible and other texts into the Slavic languages.

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