The brothers Constantine (later a monk under the name Cyril) and Methodius, originally from Thessaloniki, are sent in 862-863 by the Byzantine emperor Michael III and Patriarch Photius as missionaries to Great Moravia, at the request of Prince Rostislav, who sought to reduce his country's dependence on East Frankish priests. Since the Slavic language could not be adequately written with either the Greek or Latin alphabet, Cyril creates a completely new alphabet, the Glagolitic, specifically designed to represent the sounds of Old Church Slavonic. With it, Cyril and Methodius translate the Bible and the liturgy into Old Church Slavonic, allowing for the first time Christian worship in the vernacular Slavic language instead of exclusively in Greek or Latin. After the deaths of both brothers (869 and 885 respectively), their disciples are expelled from Moravia and move to the First Bulgarian Empire, where the Cyrillic alphabet — developed by their Bulgarian disciples, including Saint Clement of Ohrid, in honor of Cyril, but not by the brothers themselves — would gradually replace the Glagolitic.