Ofcourse there were lower classes of people in Europe too, there were prisoners, etc. Then why only Africans and black people? Was this due to color differences and thus racism? Or due to advanced warfare of Europe which could threaten Africans to work for them?
Hi -- not discouraging more answers, but there's a lot in this section of our FAQ which may be of interest to you.
There are many factors for why this is the case so here are the most likeliest reasons as to why. Note this criteria I am about to give may have some inaccuracies to take this with a grain of salt, without further ado here are some of the reasons why Africans are used as slaves.
Reason 1 they are non christians
Reason 2 they have a higher resistance to tropical diseases were cash crops usually grow
Reasont 3 they can handle any environment be it cold or hot they can handle it
Reasont 4 is that West Africa is nearby and Transporting west Africans to the new world is easier and cheaper than getting Asians slaves.
So yeah, here are the likeliest reasons feel free to disagree.