I'm sure someone said this, but you do know tribes in Africa would capture black people and they were black people and keep them as slaves until the European colonies started buying them from the tribesman. There's no such thing as a clean race only clean people.
Sure that happened, when the Europeans still hadn't show their true intentions in the beginning of the trafficking, those were the times where the Europeans could only take a few Africans back to Europe on their boats...the times in which they were still duping the African Kings (who actually thought they had gained new and foreing allies) and people into thinking they were fair and full of good intentions.
Well in my country they say: "The one who's full of good intentions is the Devil" and no, that is not my declaration of hate. It is to show that Africans fucked up as soon as they decided to "trust". Because you see, African's are no different than Asians or Native Americans or Europeans, they also practiced slavery against one another (black kings with black slaves) and they also tried to conquer each other's lands.
Things got out of hand when the African Kings decided to do business with Europeans and started trading slaves with whatever the Europeans would bring them (clothes, mirrors, wine, etc).
Then religion came into the game, yes, Christianity (catholicism to be precise), and psychology tactics started being played, the Europeans started telling the Kings that they were different, closer to them than their subordinates (Kings started getting European nationalities and beingattributed high European positions) and while the King was being fooled, the Europeans started rampaging the African people from the villages, that's when the Kwata Kwata wars started.
I do agree with your last statement, that there is not such a thing as a clean race and only clean people, but there are "not so clean" people who do think in terms of race (blacks, asians and whites alike) and unfortunately most "not so clean people" have power, so there.
PS: When it comes to African history, I'm free to provide information anytime and anyday.