In the seventh century, a group of magnates formed what was later called by the Byzantines, the Great Moravia, a rich and prosperous country stretching through the whole area of today’s Czech Republic. A big issue that the growing empire had to face was paganism, dividing the area from the rest of the world both politically and economically. King Rastislav embraced two scholars, Cyril and Method sent to him by the Byzantine emperor to help spread Christianity and literacy among the people. The reason why Great Moravia only lasted two centuries, was constant pressure from the Franc conquerors who wanted to invade the country. Militarily weakened Moravia perished in 907 when it was attacked by Hungarian migratory tribes.