Cyrillic Alphabet. — The Cyrillic alphabet was introduced into Old Slavic literature in Bulgaria at the turn of the 9th to the 10th century. It was modeled on the Greek majuscule script as found in 9th–10th century liturgical texts. For Slavic sounds lacking Greek equivalents, letters were borrowed from the Glagolitic alphabet (q.v.).
The authorship of the Cyrillic alphabet is not established; it was later erroneously attributed to St. Cyril, apostle of the Slavs, from whom it takes its name. Since it is simpler than the Glagolitic, its use prevailed in Old Slavic and Church Slavonic literature. It is still employed today in the liturgical books of the Byzantine-Slav rite. Modernized, especially in Russia under Peter the Great (graždanskij šrift: civil type), it is still used by Russians, Ukrainians, Serbs, and Bulgarians.