[Illustration: LIBUS̆A’S BATH JUST BELOW THE VYS̆EHRAD.]
But the Greek missionaries found that the want of a written language prevented them from giving their Slavonic converts full instruction in the details of the Christian creed. Methodius, therefore, called in the help of his brother Cyril, who had been occupied in the conversion of the Chazars, a people whose country lay a little to the north of the Bulgarian kingdom.
Cyril was a learned monk, who had been trained at the Court of Constantinople, and was well skilled in various languages. Taking the Greek alphabet as his basis, but altering its form, he invented a written language for the Slavonic race, into which he translated a liturgy, several books of the Bible, and some of the early Fathers.
The news of the conversion of the Bulgarians quickly came to the ears of Rostislav, for the great Bulgarian kingdom touched the eastern side of Moravia; and the recent alliance had brought the two peoples into closer intercourse. Unwelcome as Christianity had seemed to the Moravians, when presented to them as a demand of Frankish invaders, and taught in an unknown tongue, its lessons came with a very different force when urged by pious and peaceable monks, recommended by friendly kinsmen, and expounded in a language intelligible to the converts. Rostislav no doubt quickly perceived that the new teaching might form a valuable link in the alliance of the Slavs against their enemies. He appealed to the Emperor of the East to send Cyril and Methodius to Moravia; and, when they arrived at the town of Devina, Rostislav and his followers went out to welcome them; and after Cyril had retired from the mission, Methodius was recognised by the Pope as Archbishop of Moravia and Pannonia.
But troubles very soon began for the new-comers. The German party in Moravia were resentful at the introduction into the churches of what they considered a barbarous language; and they saw danger to their power, both in the adoption of a ritual which was understood by the people, and in the assertion of an episcopal authority which claimed to be independent of the German bishops. Nor was it only by foreigners that the influence of Cyril and Methodius was endangered; an opposition was roused even among the Moravians themselves. Svatopluk, the nephew and rival of Rostislav, seems to have accepted some kind of nominal Christianity, but unaccompanied by any change of life, or even by any great reverence for the externals of worship; and he opposed the new apostles of the Slavs with the greatest fierceness. The opposition of this ambitious prince no doubt arose at first from his desire to pose as the champion of the German party, who were undermining his uncle’s authority. According to one story he had already attempted to poison Rostislav, and having failed in that purpose he conspired with the Emperor Louis against him, made him prisoner, and sent him off to the Imperial Court to be tried. Louis threw Rostislav into prison, and put out his eyes. But Svatopluk, though he succeeded in seizing the Dukedom, did not long retain the confidence of the Emperor or the German party. He, in his turn, was deposed and thrown into prison.