After a death of the Serbian prince, his two sons took over the rule and divided White Serbs in two groups. One remained in White Serbia, while the other group migrated to the Balkans. Frankish "Chronicle of Fredegar" mentions Dervan, chieftain of the Serbs, in c. 631, who may be the first Serb mentioned by name in history. Dervan is considered to be the father or, more likely, brother of the nameless prince who led the White Serbs into the Balkans.