though St. Cyril was, it is improbable that he distinguished between the Slavonic dialect spoken around Salonika and that of Moravia, whither his emperor sent him, and from the interminable controversies that the origin and history of this alphabet have provoked one fact emerges clearly, namely, that the dialect, for the reproduction of which this alphabet was composed, was not that of the Čech-Slovak inhabitants of Moravia, to convert whom St. Cyril had been called, but belonged to the southern division of the Slavonic languages and was that from which modern Bulgarian is descended. It is for this reason that the Slavonic language of that ecclesiastical literature, which is the earliest form of any Slavonic language that has survived, is now by general consent called Old Bulgarian. With the growth of the Western Church and the invasion of the Asiatic Magyars all trace of the results achieved by Byzantine missionary activity in Moravia, north of the Danube, disappeared, but the conversion of more than half of the Serb race from Byzantium and their secular allegiance to the Eastern Church are symbolized in the permanent adoption and use by them of the Cyrillic alphabet.
This alphabet, which, as already explained, originally only corresponded, and was only designed to correspond, to the sounds of the Bulgarian language, but had been in use from the time of their conversion also amongst all orthodox Serbs, was in the first half of the ninth century amplified and adapted to suit the phonology of his mother-tongue by the great Servian philologist and author, Vuk Stefanović Karadžić. In carrying out his scientific reformation of the Cyrillic alphabet, he had to face the embittered opposition of all classes, but especially of ecclesiastical circles, who termed the letter J, very reasonably borrowed by Vuk from the Latin alphabet, 'the Devil's Letter'; but, thanks to his efforts, Servian is the only one of the Indo-European languages besides Sanskrit to enjoy the use of an alphabet that accurately and without auxiliary diacritic signs corresponds to all the sounds of which it is composed.
