Another factor, yes.
A few of my fellow students at university who were Indian/Pakistani were very racist about black people. This wasn't taught to them by fucking colonialism - they come from countries where 'caste' is prevalent and the tone of your skin often tells people from which caste you belong.
Same in China - especially in the major, developed cities they look down upon darker-skinned Chinese because it suggests you're a farmer/rural poor worker (you spend a lot of time in the sun). They love whitening their skin with moisturiser in some parts of China because they feel it makes them look more 'affluent'. If they feel that way about darker-skinned Chinese people, IMAGINE how low down the ladder they see African people as being? Basically, some Chinese consider them to not be subhuman.