You can temporarily conqueror a people by force but to maintain it long term requires a different mental strategy. Using Cultural Diffusion which is a method whereby the captor or invader does not seek to remove the teachings of the captive but instead seek to overlay their own system with that which already exists. This was made possible by looking for similarities or likenesses between the two societies and focusing on those similarities instead of the differences as they (the captors) are able to say God & Allah are one and the same, Moslems are able to say Obatallah & Allah are the same, Zeus & Jesus are the same, etc. This ensures that the population is easily converted with little resistance and any who did are seen by their own people as being against that which is right.
Nubians need to learn about their own ancient religious system and heritage which called Atonism!
For more information, read:
"The Original 12 Tribes of the Scriptures" $39
"Identity Theft: The Blessing vs The Curse" $37