It's actually not, whether you're talking about individual freeing of slaves (which has basically been a thing since slavery was instituted at all) or nation-scale emancipations.
A careful reading of that timeline and its sources shows that all the "emancipations" listed before the 18th century are highly localized and/or short-lived, so I would agree that the widespread concept of freedom from slavery as an inalienable right is fairly modern.
> So if freedom from slavery. So?
It's actually not, whether you're talking about individual freeing of slaves (which has basically been a thing since slavery was instituted at all) or nation-scale emancipations.
http://en.wikipedia.org/wiki/Abolition_of_slavery_timeline