Wasn't Slavery Corrected when it was abolished? Who should apologize?

So many think oh yeah we're *whatever race* so we deserve an apology. Well, then every race on the face of the Earth deserves an apology. this is not a racist comment. what i am saying is everyone kept slaves, including the africans in africa. IN FACT, it was the african tribal leaders who sold the white man the slaves in the first place! Even "civilized" people like the Greeks kept slaves. and these men were treated worse than the African people. Not only did every race keep slaves, but every race had a way of capturing. Usually prisoners of war were slaves, until buying became popular.