But Europe's is the only civilization in the whole of history that voluntarily abolished chattel slavery.

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So was chattel slavery and the back-breaking manual labor that kept these massive plantations thriving.

CNN: Django, in chains

And once bonded, the threat of violence and the limitations on personal freedom involved make the practice in effect no different from chattel slavery.

ECONOMIST: Still with us

Anti-Slavery International's Beth Herzfeld told the BBC earlier this year that chattel slavery, involving a class of hereditary slaves, still existed in parts of Africa, and bonded labour remained common in South Asia.

BBC: Undated depiction of slaves in captivity