Did Slavery Exist Before Europeans

Some form of slavery existed in Africa before Europeans arrived; however it was a system of temporary consequences. People were enslaved as punishment for a crime, to pay a debt, or as captives of war. African slavery was very different from what was to come later with the Europeans because it was not for personal gain and inhumane suffering of others. Unlike European slavery, African slaves could work to buy their freedom and their children were not automatically slaves. Captive Africans and their descendants paid with their blood and sweat for the phenomenal expansion of human possibilities in the Atlantic world.' (Robin Blackburn)
Europeans changed the scale of slavery. Did slavery exist before the Europeans began to exercise its power