The Slav peoples were organized along tribal lines, each headed by a zupan (chieftain). In this part of the Adriatic littoral, from the time of the arrival of the Slavs up to the 10th century, these local magnates often were brought into unstable and shifting alliances with other larger states, particularly with Bulgaria, Venice, and Byzantium. Between 931 and 960 one such zupan, Ceslav, operating from the zupanija of Zeta in the hinterland of the Gulf of Kotor, succeeded in unifying a number of neighbouring Serb tribes and extended his control as far north as the Sava River and eastward to the Ibar. Zeta and its neighbouring zupanija of Raška (roughly modern Kosovo) then provided the territorial nucleus for a succession of Serb kingdoms that in the 13th century were consolidated under the Nemanjic dynasty. (See Serbia: Medieval Serbia.)
Inače, još i prije nego što je nastala država u Duklji/Zeti pod vodstvom Vojislavljevića koji su bili srpskog travunskog porijekla, nad njom su vladali vlastimirovićevski vladari. Jedan od starosrpskih prijestonica je bila Gradina. Tek poslije 950. odnosno 960. godine nastaje država u Duklji, raspadom srpske države u jeku bugarske invazije.