In the 700's, the religion of which allows slavery, arrived in africa and was responsible for enterprising africans selling their fellow countrymen into slavery.

The Islam religion is responsible for Africans to allow slavery. During that time, persons who are not able to pay their taxes could be slaves until they pay their taxes by being slaves. In the Islamic view of slavery as per their Quran and Hadith, it is said to be that slavery exist before. It also shows that in Quran, slavery means payments of the sin of the person.

voter turnout, 2006-2012

definitely a for sure. ill see and update if i get the answer