That's the easy answer, but I would suggest it's overly simple. Africans are people, and in my experience are not much more 'savage' than you'll find in any country. That is, most 'savage' behaviour is carried out by a group or class of twits. The difference is only that unlike in Britain they aren't dressed in Burberry and aren't marginalised. They run the show because the non-twits are so badly organised.
They are savages because they still believe in witchcraft and other similar pre-christian practices. We in the west have moved on and are more refined. We have nukes, systematic torture with the best equipments, we commit genocide in the name of ideologies that have been sprung by the brightest minds that the universities have offered. We have impaled 20000-40000 turks just to prove that they aren't welcomed in walachia, and had wars that lasted 100 years in the name of who has the right to sit in a special chair in a special place.
They are simple and barbaric, since they are stuck in such ways that were abandoned thousands of years ago in the rest of the world. Get with the times.
Wait, does that mean we're engaged?