Bury the Chains: Prophets and Rebels in the Fight to Free an Empire’s Slaves by Adam Hochschild is a brief, readable account of the movement that ended slavery in the British Empire. It’s worthwhile, because it makes two points that are too often forgotten. First, that all the tactics of organized social movements (boycotts, pamphlets, petitions, etc.) that we take for granted were pioneered by the anti-slavery movement. Secondly, that when the movement started in the 1780s, the vast majority of the world’s inhabitants were slaves by any meaningful definition. Too many things are still wrong in the world, but at least that is no longer true.