METHODIUS (c. 825–885), the apostle of the Slavs, was a native of Thessalonica, probably by nationality a Graecized Slav. His father’s name was Leo, and his family was socially distinguished; Methodius himself had already attained high official rank in the government of Macedonia before he determined to become a monk. His younger brother Constantine (better known as Cyril, the name he adopted at Rome shortly before his death) was a friend of Photius, and had earned the surname “the Philosopher” in Constantinople before he withdrew to monastic life. Constantine about 860 had been sent by the emperor Michael III. to the Khazars, a Tatar people living north-east of the Black Sea, in response to their request for a Christian teacher, but had not remained long among them; after his return to within the limits of the empire, his brother and he worked among the Bulgarians of Thrace and Moesia, baptizing their king Bogoris in 861. About 863, at the invitation of Rastislav, king of “Great Moravia,” who desired the Christianization of his subjects, but at the same time that they should be independent of the Germans, the two brothers went to his capital (its site is unknown), and, besides establishing a seminary for the education of priests, successfully occupied themselves in preaching in the vernacular and in diffusing their translations of Scripture lessons and liturgical offices. Some conflict with the German priests, who used the Latin liturgy, led to their visiting Pope Nicholas I., who had just been engaged in his still extant correspondence with the newly converted Bulgarian king; his death (in 867) occurred before their arrival, but they were kindly received by his successor Hadrian II. Constantine died in Rome (in 869), but Methodius, after satisfying the pope of his orthodoxy and obedience, went back to his labours in “Moravia” as archbishop of Syrmia (Sirmium) in Pannonia. His province appears to have been, roughly speaking, co-extensive with the basins of the Raab, Drave and Save, and thus to have included parts of what had previously belonged to the provinces of Salzburg and Passau. In 871 complaints on this account were made at Rome, nominally on behalf of the archbishop of Salzburg, but really in the interests of the German king and his Germanizing ally Swatopluk, Rastislav’s successor; they were not, however, immediately successful. In 879, however, Methodius was again summoned to Rome by Pope John VIII., after having declined to give up the practice of celebrating mass in the Slavonic tongue; but, owing to the peculiar delicacy of the relations of Rome with Constantinople, and with the young church of Bulgaria, the pope, contrary to all expectation, ultimately decided in favour of a Slavonic liturgy, and sent Methodius (880) back to his diocese with a suffragan bishop of Neitra, and with a letter of recommendation to Swatopluk. This suffragan, a German named Wiching, unfortunately proved the reverse of helpful to his metropolitan, and through his agency, especially after the death of John VIII. in 882, the closing years of the life of Methodius were embittered by continual ecclesiastical disputes, in the course of which he is said to have laid Swatopluk and his supporters under the ban, and the realm under interdict. The most trustworthy tradition says that Methodius died at Hardisch on the March, on the 6th of April 885. He was buried at Welehrad (probably Stuhlweissenburg). The Greek Church commemorates St Cyril on February 14 and St Methodius on May 11; in the Roman Church both are commemorated on March 9. Their canonization (by Leo XIII. in 1881) is noteworthy, in view of the fact that Gregory VII. and several other popes condemned them as Arians. After the death of Methodius much of his work was undone; his successor Gosrad, a Slav, was expelled, with all the Slav priests, and the Latin language and liturgy supplanted the vernacular. On the 5th of July 1863 a millennial celebration of the two brother apostles was held by the people of Bohemia and Moravia.

See Schafarik’s Slawische Alterthümer; L. K. Götz, Geschichte der Slavenapostel Konstantinus und Methodius (Gotha, 1897); N. Bonwetsch, Cyrill und Methodius, die Lehrer der Slaven (Erlangen, 1885), and art. in Hauck-Herzog’s Realencyk. für prot. Theol. iv. 384, where the literature is cited; G. F. Maclear, Conversion of the Slavs (London, 1879).