Saints Cyril and Methodius were two Byzantine Greek brothers born in Thessaloniki in the 9th century. They created the Glagolitic alphabet, which was suited to match the specific features of the Slavic language. Its descendant alphabet, the Cyrillic alphabet, is still used by many languages today. Through their work they influenced the cultural development of all Slavs, for which they received the title "Apostles to the Slavs". They became missionaries of Christianity among the Slavic people of Great Moravia and Pannonia.
After their deaths, their pupils continued their missionary work among other Slavs. They were accepted by the Bulgarian ruler Tsar Boris I, who was actually the one to give them the recourses to train students and spread widely their work.
Both brothers are honored in the Eastern Orthodox Church as saints with the title of "Equals to the Apostles". In 1880, Pope Leo XIII introduced their feast into the calendar of the Roman Catholic Church. In 1980, Pope John Paul II declared them co-patrons of Europe together with Saint Benedict of Nursia.
Selected cognates
The following is a very brief selection of cognates in basic vocabulary across the Slavic language family, which may serve to give an idea of the sound changes involved. This is not a list of translations: cognates have a common origin, but their meaning may be shifted and loanwords may have replaced them.
| Proto-Slavic | Russian | Polish | Czech | Serbo-Croatian | Bulgarian |
| *uxo (ear) | ухо (ukho) | ucho | ucho | уво / uvo; uho | ухо (uho) |
| *ognь (fire) | огонь (ogon') | ogień | oheň | огањ / oganj | огън (ogan) |
| *ryba (fish) | рыба (ryba) | ryba | ryba | риба / riba | риба (riba) |
| *gnězdo (nest) | гнездо (gnezdo) | gniazdo | hnízdo | гн(иј)ездо / gn(ij)ezdo | гнездо (gnezdo) |
| *oko (eye) | око (oko) | oko | oko | око / oko | око (oko) |
| *golva (head) | голова (golova) | głowa | hlava | глава (glava) | глава (glava) |
| *noktь (night) | ночь (noč') | noc | noc | ноћ / noć | нощ (nosht) |
Saints Cyril and Methodius Day
It commemorates the creation of the Slavonic Glagolitic and Cyrillic alphabets by the brothers Saints Cyril and Methodius. The celebration also commemorates the introduction of the Slavic language in churches. In Bulgaria it is celebrated on 24 May and is known as „The day of the Slavonic Culture and Enlightenment ", a national holiday which also honors the Bulgarian culture and literature as well as the alphabet and is celebrated in every school across the country.
