Czech historiography knows of only one school at the outset of Czech history in the 10th century — the school at the Budeč Castle — which is also believed to be the first school in this country. The existence of this school is confirmed concurrently by most of the legends about St. Wenceslas, which mention it as a place where Prince Wenceslas was educated. In this study the author has tried to prove that Budeč was not the first school in the Czech lands; but the first school in this country must be sought in the Great Moravian Empire. The existence of the first school there is linked with the beginnings of Christianity brought to Czech territory by Cyril and Methodius. The knowledge and the spreading of the Glagolitic alphabet, composed by Constantine-Cyril for the purposes of Slavonic religious services in Moravia, as well as the education of young priests necessarily called for an educational establishment. Legends about St. Cyril confirm this fact with absolute certainty. By analysing the bits of information found in these number the author draws conclusions .about the organisation, the curriculum and the number of pupils at this school, which is really the first school in this country. The author has also-formed a hypothesis based again on the interpretation of some passages in the legends about the instruction of St. Wenceslas in Slavonic liturgy, that after the expulsion of the disciples of Methodius from the Great Moravian Empire by Svatopluk, a second school of Slavonic liturgy and the Glagolitic alphabet probably came into being towards the end of the reign of the Czech Prince Bořivoj at his seating the Prague Castle. This school continued to exist throughout the 10th century. Thus Budeč school appears to be, not the first, but the third school on Czech territory.