Cyril and Methodius
9th-century Byzantine Christian theologians and missionaries

Cyril (Greek: Κύριλλος, romanized: Kýrillos; born Constantine [Greek: Κωνσταντίνος, romanized: Konstantínos]; 826–869) and Methodius (Μεθόδιος, Methódios; born Michael [Greek: Μιχαήλ, romanized: Michaíl]; 815–885) were brothers, Byzantine Christian theologians and missionaries. For their work evangelizing the Early Slavs, they are known as the "Apostles to the Slavs".
They are credited with devising the Glagolitic alphabet, the first alphabet used to transcribe Old Church Slavonic. After their deaths, their pupils continued their missionary work among other Slavs. Both brothers are venerated in the Eastern Orthodox Church as saints with the title of "equal-to-apostles". In 1880, Pope Leo XIII introduced their feast into the calendar of the Roman Rite of the Catholic Church. In 1980, the first Slav pope, Pope John Paul II declared them co-patron saints of Europe, together with Benedict of Nursia.
Early career
Early life
The two brothers were born in Thessalonica, at that time in the Byzantine province of the same name (today in Greece) – Cyril in 827–828, and Methodius in 815–820. According to the Vita Cyrilli ("The Life of Cyril"), Cyril was reputedly the youngest of seven brothers; he was born Constantine, but was given the name Cyril upon becoming a monk in Rome shortly before his death. Methodius was born Michael and was given the name Methodius upon becoming a monk in Polychron Monastery at Mysian Olympus (present-day Uludağ in northwest Turkey).
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