Vitalian, an imperial general probably of mixed Roman and barbarian descent, rebels in 513 against Emperor Anastasius I, whose fiscal stringency and promotion of Miaphysitism are widely unpopular, which allows Vitalian to quickly win over large parts of the army and the people of Thrace to his cause.

After scoring a series of victories over loyalist armies, Vitalian comes to threaten Constantinople itself, and forces Anastasius to officially recant his adoption of Miaphysitism in summer 515.

Soon after, however, as Anastasius fails to honor some of the terms of the agreement, Vitalian marches on Constantinople, only to be decisively defeated by Anastasius' admiral, Marinus.

Vitalian flees to his native Thrace and remains in hiding until Anastasius's death in 518.

As a staunch promoter of Chalcedonian orthodoxy, he is pardoned by the new emperor Justin I, who is is engaged in the negotiations with the Pope to end the Acacian Schism.