What is "zabergan"

Zabergan was the chieftain of the Kutrigurs, a nomadic people of the Pontic–Caspian steppe. His name is Iranian. Either under pressure by incoming Avars, or in revolt against Byzantine Empire, in the winter of 558, he led a large Kutrigur army who crossed frozen Danube, and was divided into three sections; one raided south far as Thermopylae, while two others the Thracian Chersonesus and the periphery of Constantinople. In March 559 Zabergan attacked Constantinople, and one part of his forces consisted of 7,000 horsemen.

The transit of such big distances in short period of time shows that the Kutrigurs were mounted warriors, and Zabergan's raiders were already encamped near the banks of the Danube. However, once again Emperor Justinian I (527–565) managed to persuade the Utigur chieftain Sandilch to attack the Kutrigurs, which resulted with decimation of one another. It is unknown if is related to the general Zabergan who in 586 defended fortress Chlomaron against the Romans.