As practiced in ancient Egypt, slavery was not about racism. It happen because of war and crimes that people did. Slavery basically means that you were a prisoner of war and the people that won the war capture you for there needs. Later on in history humans were traded for spices like sugar/canes, peppers and other important spices. That's what people did in the Triangular Trade.They had slaves doing things for other and if it wasn't don't they were whiped and hurt until they did it. Meaning they weren't treated right by others.
"Slavery is so intolerable a condition that the slave can hardly escape deluding himself into thinking that he is choosing to obey his master's commands when, in fact, he is obliged to. Most slaves of habit suffer from this delusion and so do some writers, enslaved by an all too personal style." -W.H Auden
"Slavery can only be abolished by raising the character of the people who compose the nation; and that can be done only by showing them a higher one." -Chapman, Maria Weston