Cyrillic script of Bulgaria to the European Union on 1 January 2007, Cyrillic became the third official script of the European Union, following Latin and Greek. Cyrillic is derived from the Greek uncial script, augmented by letters from the older Glagolitic alphabet, including some ligatures. These additional letters were used for Old Church Slavonic sounds not found in Greek. The script is named in honor of the two Byzantine brothers, Saints Cyril and Methodius, who created the Glagolitic alphabet earlier on. Modern scholars believe that Cyrillic was developed and formalized by early disciples of Cyril and Methodius. In the early 18th century,
Saints Cyril and Methodius Saints Cyril and Methodius Saints Cyril and Methodius (826–869, 815–885; ("Kýrillos kaí Methódios"), Old Church Slavonic: Кѷриллъ и Меѳодїи) were two brothers who were Byzantine Christian theologians and Christian missionaries. Through their work they influenced the cultural development of all Slavs, for which they received the title ""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 Orthodox Church as saints with the title of ""equal-to-apostles"". In 1880, Pope Leo XIII