Complex sentence: The Acritic songs (-- "frontiersmen songs") are the heroic or epic poetry that emerged probably from 9th century Byzantium, celebreted the exploits of the Akrites, the frontier guard defending the eastern borders of the Byzantine Empire.
Split into simpler sentences: The Acritic songs (-- "frontiersmen songs") are the heroic or epic poetry that emerged in Byzantine Empire probably in 9th century. These songs celebreted the exploits of the Akrites, the frontier guard defending the eastern borders of the Byzantine Empire.