The Bulgar people, who occupied territory considerably larger in those times than modern Bulgaria, had intermarried with the denizens and adopted the Slav language. Their two first apostles are reckoned to be Cyril and Methodius, although neither actually preached in Bulgaria. On the death of Methodius, Gorazd succeeded him in his missionary apostolate: although the extent of his territory is disputed, his relics are claimed by Berat (Albania).
Of the seven the most important for Bulgaria itself is Clement (Slovensky) of Okhrida. Born in 840, a Slav from southern Macedonia, he established a monastery at Okhrida and a bishopric at Velica not far away. He is regarded as the founder of this primatial see and the first Slav to become a bishop. His extensive apostolate took the form of education of the clergy and of the laity, to whom he preached a series of sermons in Slavonic, suitable for neophytes and explaining the principal feasts of the liturgical year. Clement died at Okhrida on 27 July 916.
His colleague Nahum succeeded him as bishop. Converted in Moravia by Cyril and Methodius, he journeyed with them to Rome and helped them with their translations into the vernacular: he is venerated in Russia as well as Bulgaria. Other companions of Clement called Sava and Angelar are also venerated with him. In different times and different places they all contributed to the fulfilment of the missionary plans of Cyril and Methodius. Feast: usually 27 July, but also in different places 17 July, 22 and 25 November.
Life of Clement in P.G., cxxvi, 1193–1240;F. Dvornik, Les Slaves, Byzance et Rome (1926), pp. 312–18;B.L.S., vii. 220–1;Bibl. SS., iv. 29–35.