Nobatia or Nobadia (; Greek: Νοβαδἰα, Nobadia; Old Nubian: Ⲛⲟⲩⲃⲁⲇⲓⲁ, Noubadia) was an ancient African Christian kingdom in Lower Nubia and subsequently a region of the larger Nubian Kingdom of Makuria. Its name is often given as al-Maris in Arabic histories.
Nobatia was likely founded by the Nobatae , who had been invited into the region from the Egyptian desert by the Roman Emperor Diocletian to help defeat the Blemmyes in AD 297. Early Nobatia is quite likely the same civilization that is known to archeologists as the Ballana culture. Eventually the Nobatae were successful, and an inscription by Silko, "Basiliskos" of the Nobatae, claims to have driven the Blemmyes into the eastern deserts. Around this time the Nobatian capital was established at Pakhoras (modern Faras); soon after, Nobatia converted to non-Chalcedonian Christianity.
By 701, Nobatia had been annexed to its southern neighbor, Makuria. The circumstances of this merger are unknown. It most likely occurred before the Muslim conquest in 652, since the Arab histories speak of only one Christian state in Nubia and reached at least as far as Old Dongola. Nobatia seems to have maintained some autonomy in the new state. It was ruled by an eparch of Nobatia who was also titled the Domestikos of Pakhoras. These were originally appointed but seem to be dynastic in the later period. Some of their records have been found at Fort Ibrim, presenting a figure with a great deal of power. However, some Arab writers refer to the merged state as the "Kingdom of Makuria and Nobatia," which might imply a dual monarchy for at least some periods.
Nobatia was the closest part of Nubia to Egypt and was the most subject to the influence of Arabization and Islamization. Over time the people of Nobatia gradually converted and married into Arab clans such as the Banu Kanz, although some remained independent in the Christian kingdom of Dotawo until its conquest by Sennar in 1504.