You shouldn't babble about topics of which you know not. There is no caste system in the regions of Africa from which most slaves were taken.
Now resume the new Indo KKK obsession of lusting after big baad blackman.
Suh, what is iboo, yoruba and hauser-all from west africa.
What do the IGBO, HAUSA, and Yoruba, have to do with caste. These are different ethnic groups with very different forms of social organization. In addition, the Hausa, located hundreds of miles from the coast, wouldn't have directly engaged the Europeans in the slave trade.