The Bulgarian alphabet is a Cyrillic alphabet and, since Bulgaria’s accession to the EU in 2007, the third official alphabet in the European Union. You can find Cyrillic letters on the euro bills side by side with the Latin and the Greek letters.
Most Slavic nations use the Cyrillic alphabet: Belarusian, Bulgarian, Russian, Serb, Macedonian, Montenegrin, and Ukrainian. Some non-Slavic nations also use it: Moldovan, Kazakh, Uzbek, Kyrgyz, Tajik, Mongolian, the people of the Caucasus and Siberia. It is also the official alphabet of the Church Slavonic language of the Eastern Orthodox and Eastern Catholic Church.
The Cyrillic alphabet is a simplified version of the Glagolitic alphabet. The Glagolitic alphabet was created under the orders of the Byzantine Empire and the Byzantine Church to be spread among the Slavic peoples, as an antidote to the Latin alphabet and the influence of the Roman Catholic Church.
The Glagolitic alphabet was created by the scholars Saints Cyril and Methodius, brothers born in Thessaloniki. In the 890s, after a few years of persecution from the Germanic clergy and the Pope, the brothers’ disciples found asylum in Bulgaria. They created the Cyrillic alphabet in order to aid their new patron, tzar Boris I, in spreading Christianity among his people. Read more about Boris I, the ruler who Christianized Bulgaria and enlarged it greatly.
The literary school of the Bulgarian Empire was very prolific. Volumes and volumes in Old Bulgarian language using the Cyrillic letters were spread across Eastern Europe, thus spreading literacy and knowledge among the Slavic nations. Today, the Church Slavonic resembles Old Bulgarian, but the Cyrillic alphabet used in different countries has adapted to fit the needs of the ever-changing local spoken languages.
We Bulgarians believe that our language and the Cyrillic alphabet are at least in part our legacy to the world (I have to say in part in order to avoid criticism from overly patriotic Bulgarians as well as criticism from opponents of the historical evidence).
On May 24th, we celebrate the Slavic alphabet!