The Cyrillic alphabet was created in the 9th century at the Preslav Literary School in the First Bulgarian Empire.

The Cyrillic script was developed around 893 AD at the Preslav Literary School in the First Bulgarian Empire under the patronage of Tsar Simeon I the Great. Though named after Saint Cyril, the alphabet was actually finalized by his students, most notably Saint Clement of Ohrid, who refined it to replace the more complex Glagolitic alphabet.The script was meticulously designed to represent the sounds of Old Church Slavonic with precision. By establishing a standardized writing system, the Bulgarian Empire reinforced its cultural independence from Byzantine influence and created a powerful tool for spreading literacy and Christianity throughout Eastern Europe and the Balkans during the Middle Ages.Today, Cyrillic is the primary script for over 50 languages, including Russian, Ukrainian, Bulgarian, Serbian, and various languages across Central Asia such as Mongolian and several Turkic languages. When Bulgaria joined the European Union in 2007, Cyrillic became the EU's third official script, alongside Latin and Greek.The Day of Slavonic Alphabet, Bulgarian Enlightenment and Culture, celebrated on May 24th, has been observed in various forms since the mid-19th century. It remains one of Bulgaria's most significant cultural events, honoring the preservation of Slavic identity through written language.