Gennadius was a Roman general and statesman who served as Exarch of Africa from 652 to 678, first under the Emperor Gregorius and later under Wamba. He was appointed to the position by his predecessor, Gregorius, who resigned in order to focus on his imperial duties.
Although at first he served Gregorius loyally, and was allowed to administer Africa without interference as a reward, he soon became disillusioned by reports of despotism and brutality towards the citizens of Italy. In 673, therefore, when Gregorius was trapped by the Goths at the Siege of Arelate and called upon Africa for aid, Gennadius refused to send any help. Gregorius died soon after, and King Wamba of the Visigoths invaded Italy early the next year.
In the chaos that followed, Gennadius could easily have taken the throne himself, but he chose not to for the sake of peace. Instead, along with Pope Adeodatus, he advised the Senate to offer it to Wamba, thus turning the Visigothic threat into a strong ally. The grateful Wamba confirmed Gennadius in his position, as well as rewarding him with various other titles and honours, and Gennadius served the new emperor faithfully until his death in 678.