 Following the onset of Muslim attacks against North Africa, it became a crucial strategic base, and for a while, in 661–668, it was the residence of the imperial court under Constans II.Constituted as a theme around 690, its governing "strategos" also came to assume control over the scattered imperial possessions in the southern Italian mainland.The island was raided thereafter, especially in the first half of the 8th century, but did not come under serious threat until the Muslims completed their conquest of North Africa and moved into Hispania as well.