One of the things I find odd about the American discourse about slavery is how rarely Americans think about slavery as an institution which existed outside America. Not only did slavery exist in the ancient world in a pre-racialised way–in which many slaves were white, and many masters were people of colour–but it also existed in many other places during the period in which it existed in America. In many of these places, slavery was abolished not by violence but by ordinary politics. Yet this is rarely acknowledged or discussed, and it is increasingly common for Americans to frame our history largely in terms of the slavery question. We don’t often ask why slavery was more contentious in the United States than in other places. That’s what I want to think about with you today.