Preslav Literary School
The Preslav Literary School (Pliska Literary School, Bulgarian: Преславска книжовна школа) was the first literary school in the medieval Bulgarian Empire. It was established by Boris I in 885 or 886 in Bulgaria's capital, Pliska. In 893, Simeon I moved the seat of the school from Pliska to the new capital, Preslav.
The Preslav Literary School was the most important literary and cultural centre of Bulgaria and all Slavs until the capture and burning of Preslav by the Byzantine Emperor John I Tzimisces in 972. A number of prominent Bulgarian writers and scholars worked at the school, including Naum of Preslav (until 893), Constantine of Preslav, Joan Exarch, Chernorizets Hrabar, etc. The school was also a centre of translation, mostly of Byzantine authors, as well as of poetry, painting and painted ceramics.
The school developed the Cyrillic script, and the earliest datable Cyrillic inscriptions have been found in the area of Preslav: in the medieval city itself, at nearby Patleina (also Shumen Province), Krepcha (present-day Targovishte Province), and Ravna (present-day Varna Province). At the latter, an unusually large number of inscriptions (330 graffiti), in Old Bulgarian and other languages, many written by lay people, some obscene, some written in parallel in Cyrillic and other alphabets, was found  prompting Umberto Eco to label Ravna a 10th-century language laboratory. Another impressive body of 10th-century Cyrillic inscriptions is presented by a number of leaden pendants, the bulk of which have also been found in the area of northeastern Bulgaria between Preslav and Varna with a periphery reaching to the north into present-day southeastern Romania.
Preslav School scriptoria were scattered over much of present-day northeastern Bulgaria, including churches and monasteries at Preslav (remains of 25 churches have been found there), Pliska, Patleina, Khan Krum, Chernoglavtsi (all in present-day Shumen Province), Ravna, Varna, and Murfatlar in Dobruja (now in Romania).
- Curta, Florin, Southeastern Europe in the Middle Ages, 500–1250 (Cambridge Medieval Textbooks), Cambridge University Press (September 18, 2006), pp. 221–222
- Silent Communication: Graffiti from the Monastery of Ravna, Bulgaria. Studien Dokumentationen. Mitteilungen der ANISA. Verein für die Erforschung und Erhaltung der Altertümer, im speziellen der Felsbilder in den österreichischen Alpen (Verein ANISA: Grömbing, 1996) 17. Jahrgang/Heft 1, 57–78
- Curta, Florin, Southeastern Europe in the Middle Ages, 500–1250 (Cambridge Medieval Textbooks), Cambridge University Press (September 18, 2006), p. 222
- The scriptorium of the Ravna monastery: once again on the decoration of the Old Bulgarian manuscripts 9th–10th c.] . In: Medieval Christian Europe: East and West. Traditions, Values, Communications. Eds. Gjuzelev, V. and Miltenova, A. (Sofia: Gutenberg Publishing House, 2002), 719–726 (with K. Popkonstantinov)
- Popkonstantinov, Kazimir, Die Inschriften des Felsklosters Murfatlar. In: Die slawischen Sprachen 10, 1986, S. 77–106.