By the 4th century, Abasgia^[1] had moved north and was now subject to the Byzantine Empire. In 542, the Byzantine army left Abasgia, and around 548, Abasg Euphrates arrived in Abasgia as the Byzantine ambassador, after which Christianity became the official religion in Abasgia,^[2] but did not become widespread among the inhabitants.

During the Persian-Byzantine wars, the Abasgians supported the Sasadins, hoping to free themselves from the power of Byzantium.^[3] Thus, in 550, Abasgia was involved in an uprising against Byzantium. The result of the uprising was the division of Abasgia into two parts — the eastern, whose ruler became Skeparn, and the western, whose ruler became Opsit. Skeparn soon received the support of the Sasanian court, and Opsit prepared for defense against the Byzantine troops under the command of Vilgand and John the Armenian. The following year, the Byzantines forcibly restored their power in Abasgia.^[4] During the Lazian Wars, the Byzantines built the fortresses of Sebastopolis and Pitiunt. The Byzantine government relied on a system of fortresses, the loyalty of the local nobility and the church organization.

In the 7th century, Byzantium ceded the lands of Lazica to the Abasgians.^[5] At the end of the 8th century, taking advantage of internal upheavals in the empire, the Abasgians, with the help of the Khazar Khaganate,^[6] freed themselves from the power of Byzantium, since that time power has passed from the Anosid dynasty to the new local Leonid dynasty, who at the end of the 8th century assumed the title of King of Abkhazia.