Black people are hardly the only group to have ever suffered under slavery and to have recovered from it successfully. A little group of people called the Jews seem to have done quite nicely for themselves after centuries of slavery, hatred and an attempted genocide.
Another group, the Slavs, were so widely enslaved for so long that the very word "slave" is derived from their name.
Slavery has existed in just about every culture and empire throughout history. Conquering armies would often enslave the people that they conquered - regardless of the colour of their skin. White Europeans have enslaved other white Europeans and even blacks in Africa have enslaved other black Africans.
http://en.wikipedia.org/wiki/Slave_trade