After a long period as a Roman client state, the Bosporan kingdom succumbed to the Huns, who defeated the nearby Alans in 375/376. With the collapse of the Hunnic Empire in the late 5th century, the area passed within the Roman sphere once again but was taken by the Bulgars in the 6th century. Following the fall of the city to the Khazars in the late 7th century, it was rebuilt as a fortress town and renamed "Tamatarkha". Arabic sources refer to it as "Samkarsh al-Yahud" (i.e., "Samkarsh of the Jews") in reference to the fact that the bulk of the trading there was handled by Jews. Other variants of the city's name are "Samkersh" and "Samkush".