The new X-Group culture occupied northern Nubia
Great tomb complexes built at Qustul around 370–400AD and across the Nile at Ballana around 400–500 AD mark a new material culture that appeared in northern Nubia after Meroitic rule ended there. Archaeologists call the new culture X-Group. Like the tumuli at Kerma 2000 years before, the tombs were earthen mounds over elaborate substructures that contained wealthy royal burials including sacrificed retainers. Horses and camels were also sacrificed and were buried in the shaft of the tomb or in separate pits. Texts written in Greek identify this kingdom as Noubadia. The Noubadians were almost certainly a group of Nubians who migrated into the region from the south or the west around 370 AD.
The Noubadians defeated the Blemmyes to control northern Nubia
When the Noubadians moved into northern Nubia, they found people called Blemmyes by classical writers already established at Kalabsha just south of the 1st cataract. Descendants of the ancient Medjay from the eastern desert, the Blemmyes had taken over an area earlier controlled by the Romans. Conflict between the Blemmyes and the Noubadians ended with the victory of Silko, king of the Noubadians.