The fourth century CE has seen the rise of three separate kingdoms in the area previously known as Meroe: Nobadia, Makuria and Alwa. All of them converted to Christianity in the sixth century CE. Then probably at the end of the seventh century Nobadia and Makuria merged together to form one state entity. The heyday of the Nubian kingdoms lasted ca. between 850 until 1050.
Nobadia is the northernmost of three kingdoms. It spread from the first to the third Nile cataract in its heyday, from Aswan to the region Dongola. The dawn of Nobatia dates back to the end of the fourth century. The fall of Meroe brought to life in Lower Nubia two competing chiefdoms: Blemmyan and Nobadian. In ca. 420, Olympiodorus of Thebes, a Roman historian, visited the Blemmyes. According to his account, despite controlling the Nile valley the Blemmyan king preferred to remain in the desert. At the same time the Nobades, started an expansion to the north. As a result their territories reached the border with the Byzantine Empire, which allowed for an increase of the volume of trade and an influx of new political and religious ideas. In the middle of the fifth century Nobades controlled the whole territory between the first and second Nile cataracts. Then, they directed their military expansion to the south and in the sixth century they held sway as far upriver as the third cataract. At the beginning of the sixth century, the Nobadian elite strengthened its position within the multiethnic society, and searched for effective forms for integration of the state and its peoples, and reached for the Christian religion. The king of Nobadia converted officially in 543. The capital of Nobadia was located at Faras.
The political and social center of the kingdom was located in the area between the Third and Fourth Cataracts. Dongola, the capital of the kingdom, was located south from the third Cataract, its first political centre, however, was located in El Zuma (both sites are excavated by the missions of PCMA). The beginnings of state formation in Makuria go back to the fourth decade of the fourth century and are attested in inscriptions of the Axumite king Ezana. His mighty army was held off by the Red Noba just after it had crossed Bayyuda.
Makuria, like its northern neighbor Nobadia, converted to Christianity sometime around the middle of the sixth century. Reportedly the king was baptized by a mission sent by the emperor Justinian. Both kingdoms united at some point in the seventh century CE, beginning of the eighth at the latest. In 641 and 652 the Nubians were one of the few peoples capable of repelling the Arab invasions. Both sides of the conflict signed an agreement (called the baqt) that lasted for the next five hundred years regardless of who ruled Egypt and what Islamic group prevailed.
The origins and history of Alwa the most southern of Byzantine Nubian kingdoms are very poorly known. The ethnicity of the founders of the new realm is obscure, but Alwa is considered a Nubian kingdom, as it was probably created by the Black Noba. They are mentioned in the inscription of Ezana, the king of Axum who invaded the Nile Valley in the fourth century CE.
The capital city of Alwa, Soba is the only excavated site of the Kingdom (currently by the mission of PCMA). Soba must have also been an important trade center, as it is confirmed by the presence of Muslim traders. According to Arab historians in Alwa were located large monasteries and rich churches.