found a great source about the medieval Sudanese kingdoms and the surrounding areas through the eyes of a contemporary historian named Al-Maqrizi. I avoid using the word nuba because it becomes clear this is a very diverse land and the Nubians are just one piece of a much larger society even in their biggest states.
they are interesting culturally and are unique in a spiritual, societal and architectural sense. the land had a very diverse population of so many peoples that even they did not know the numbers and names of many of the tribes that inhabited the Nile. the Nile itself and its floods are a great mystery that they go to great length to figure out, there are many instances of attempts by their kings to map out the Nile and its origins as well as seeking wisdom from people as diverse as the Indians and romans to understand why it floods:
"Then there is the Green Nile (an-Nīl al-akhḍar), a river which flows from the south-eastern direction. It is intensely green, very transparent in colour, so that one can distinctly see what kind of fish there are in its depths. The taste [of the Green Nile water] is different from that of the [White] Nile; he who armies from it soon becomes thirsty. The fish is the same in ail (these rivers), but its taste is different. During the flood season such kinds of wood as teak (as-sāj), log-wood (al-baqm), al-qānāʾ (?) (ghātā) and a wood which smells like the olibanum (labān), float downstream. Also large logs are brought down which can be worked into nalms for boats. This (kind of) wood also grows on its banks. It is also related [by al-Aswānī] that the wood of frankincense (bakhūr) is found [in the flood waters].
He said: - I saw that some planks (siqālāt) of sāj, which are carried during the flood season, bear some strange signs. These two rivers, viz. the White and the Green, meet near the capital of the sovereign (mutamallik) of the country of 'Alwa and each of them keeps its own colour for about one day’s journey, after which they mingle up. Their waters, when they meet, throw up big waves. He said: - I spoke with someone who took water from the White Nile and poured it into the Green Nile: the water [of the White Nile] remained for one hour the colour of milk before it mingled up. Between these two rivers is an island, the end of which is not known, nor does anybody know the end of these two rivers. The width of the first one is known [at the beginning], but further on it expands and its width increases as much as one month’s journey, and further on its width has not been explored at all, for the peoples who live there, fear one another in fact, many races (ajnās) dwell on these two rivers.
He [Aswānī] said: [Someone] told me that some kings (mutamallik) of the country of 'Alwa set out to visit the [p. 612] extreme frontier [of the island], but they failed to reach it after a number of years, and that, on its southern extremity, there is a race who, during the day-time, dwell together with their beasts in houses [built] like vaults, under the surface of the ground, because of the excessive heat of the sun, and come out during the night. Among them there are people who go naked."
Mas’ūdīMaqrīzī here reviews the opinions of the ancient philsophers on the cause of the Nile flood. said: The Indians (al-hind) say that the flood of the Nile and its decrease depend on the torrential rains. We know that this is true because [it occurs regularly] in connection with the stars (al-anwāʾ) causing [p. 594] the rainy season and thunderstorms. The Rūm said that the Nile neither increases nor decreases, and that the flood and its ebb are due to the many [hidden] springs which feed it. The Copts say that the increase and the decrease are caused by some springs on the coast, which can be observed by those who travel and explore its upper course. Others say that the Nile neither increases nor decreases, but that its flood is due to the wind blowing from the north, which stops its water and forces it to overflow into the countryside. Others say that the Nile flood is caused by a wind blowing called Mullathan (muln: B.: Moltan), which brings the rain-carrying clouds from below the equator; therefore it rains in the countries of the Sūdān, the Ḥabasha and the Nūba, and the mass of these waters reaches Miṣr at [the time of] the increase of the Nile and Irrigates it. (W.I, 1, ch. XVII, §13, pp. 255 - 256; B., p. 167).
while they have many cool aspects such as mystical and wandering kings, widespread trade routes that reached from Iberia to India and the long-standing treaty of baqt, ultimately, they seem similar to the Abbasids in that they didn’t really do much from an Aoe campaign perspective. they were regarded as peerless archers but that’s the limit of their military exploits.
there wasn’t a whole lot of conquering and their kingdoms failed due to societal upheaval and weakening of authority as well as immigration rather than any invasion from a foreign power. they just kind of existed doing their own thing before silently collapsing and didn’t seem to leave a huge impact on the remaining world at large.
they wouldn’t be bad as a civilization, but I think they would fit in more with games like civ 6 and humankind where their culture, mysticism, reliance and exploration of the Nile, surprisingly vast trade ties and preference for diplomacy can really shine rather than in a game like aoe. there are probably more impactful African civs during the time period that would fit in better with aoe gameplay. the age of pharaohs and pyramids are longer over at this point.
how would you make a religious trading civ with a penchant for exploration and diplomacy interesting in a game about killing your opponent’s units and destroying their landmarks?