What is a slave and how far back do you have to go before it doesn't count anymore? I mean, when the Normans conquered England they enslaved most of the population and that remained the case for many hundreds of years. My ancestors were all agricultural labourers so I am definitely the descendent of slaves. Yet, nobody is demanding an apology, let alone restitution off the French. And before anyone claims that nobody is affected by medieval serfdom anymore, I would point out that over half of the land in England is still owned by the descendants of the slave owners.
My point here is not that the English are blameless (they obviously are not), but that all the rich and powerful of every nation or tribe that has ever existed were, at heart, evil bastards.