An important role in the history of medieval Europe was played by the Slavs. They settled in Central, Eastern and South-Eastern Europe and were divided into western, eastern and southern.
Slavic tribes lived during their stay and in the north of Europe – in the basin of the river. Laba, and on the Baltic coast. But they were crowded with francs, and later – German knights. Until the end of the XII century. The Germans established themselves on this territory. The Polabo-Pomorie Slavs dissolved among the conquerors – they lost their language and customs.
In the second half of the first millennium, Slavic states appeared. The first was the principality of Samo, which was inhabited mainly by Czechs, morals and Slovaks. But it soon broke up into independent principalities.
Almost until the end of the first millennium Slavs professed paganism. But the course of history persuaded that it was time to accept the faith of Christ, to join the Christian world. And for this it was necessary to learn how to read Christian books. In the IX century. Prince of Great Moravia Rostislav turned to Byzantium with a request to send Christian preachers who would teach the Slavs Christianity in their native language. Such preachers were found. These were the brothers Cyril and Methodius, born Greek and Bulgarian. They knew the Slavic language. In 863, Cyril and Methodius, on the basis of Greek letters, developed the Slavic alphabet and translated several Christian books into the Old Slavonic language. Thus began the time of Byzantium’s powerful cultural influence on the Slavic world.
Cyril and Methodius were born in a Greek city, which the Slavs called the Thessalonica. Therefore they were called “brother of the brothers”. These Bulgarian enlighteners have developed only one Slavic alphabet, whereas it is known that the Slavs used two alphabets: Glagolitic and Cyrillic. Which of them, the Glagolitic or the Cyrillic alphabet, was developed by the “brother’s brothers” – it is not known exactly.