Sclaveni
The Sclaveni (in Latin) or Sklabenoi (various forms in Greek) were early Slavic tribes that raided, invaded and settled in the Balkans in the Early Middle Ages and eventually became one of the progenitors of modern South Slavs. They were mentioned by early Byzantine chroniclers as barbarians having appeared at the Byzantine borders along with the Antes (East Slavs), another Slavic group.