I’m well aware of the baqt treaty, Nubians kidnapped and sold Southerners from the Nuba mountains after signing it, not Nubia itself.Not true at all. Sudanese people were enslaved. In the 7th century nubian christians won a few battles against the invading muslim arabs, but they were forced to sign a treaty with the arabs in order to avoid being invaded again. According to this treaty called baqt Nubian had to send slaves to the arabs in Egypt in exchange arabs promised to leave them alone, this treaty went on for 7th centuries. Each year nubians sent slaves.
Today most arab sudanese tribes are the product of intermarriage between arabs and nubians. Nubian slaves were exported all over the arab world.