Rostislav

Rostislav of Great Moravia sought help from the emperor, who (presumably through the patriarch) in about 862 sent two brothers, Constantine (later called Cyril; c. 827–869) and Methodius (c. 825–884), from Constantinople to Moravia. They provided Scriptures and liturgy in the mother tongue of each…

Mojmír’s successors, Rostislav (reigned 846–870) and his nephew Svatopluk (reigned 870–894), extended their territory to include all of Bohemia, the southern part of modern Poland, and the western part of modern Hungary, thereby creating the state of Great Moravia. Rostislav also invited the Byzantine missionaries Cyril and…

His successor (after 846), Rostislav, consolidated the country and defended it successfully. His relations with the East Frankish empire (since 843 under Louis the German) were determined by political considerations and by the advance of Christianity into the Slavic areas. The bishoprics of Regensburg,

In 863 its prince, Rostislav, invited St. Cyril and his brother St. Methodius to create a national church with a language and writing of its own. Prior to that time some Christian texts in Moravia might have been translated into Slavic from Latin (and partly perhaps from Old High…