In the middle of the 6th century, during the reign of Byzantine emperor
Justinian I (d. 565), a fortress of
Arsa () in the province of
Dardania was refortified, as attested by historian
Procopius. At the beginning of the 7th century, Byzantine rule collapsed, and the region was settled by the
Slavs. Up to the middle of the 10th century, the fortress of
Ras was a borderline stronghold between the
Principality of Serbia and
First Bulgarian Empire, as attested by the Byzantine emperor and historian
Constantine VII Porphyrogenitus (d. 959) in his work
De Administrando Imperio. The earliest possible date of later Byzantine invasion of Rascian region and the creation of a province is around 971, when Byzantine armies
conquered Bulgaria and re-established Byzantine supreme rule over the interior of
Southeastern Europe. One of the newly formed administrative units was the Catepanate of Ras. It was established as a Byzantine stronghold in Serbian lands, but its territorial jurisdiction can not be precisely determined, but Serbia probably also was conquered. The Catepanate was short-lived, as well as the Byzantine rule in the rest of Bulgarian and Serbian lands. After the death of emperor John (976), a successful uprising started in the South Slavic provinces of the Byzantine Empire, led by
Cometopuli, resulting in total breakdown of Byzantine power in the region and the restoration of the
Bulgarian Empire. The main sources for the organization of the Catepanate of Ras is a
seal of a
strategos of Ras, dated to the reign of Byzantine Emperor
John Tzimiskes (969–976). The seal belonged to
protospatharios and katepano of Ras named John. After 976, the region was dominated by the restored
Bulgarian Empire, that had complex relations with neighbouring Serbian princes. Byzantine rule in the region was restored in 1018, under emperor
Basil II (d. 1025), and new administrative units in Serbian lands were created, including new
themes, one centered in the region of
Syrmia to the north (
Theme of Sirmium), and other in central
Serbia (
Theme of Serbia). ==See also==