Abstract: International legal historians write with passion and their texts can bristle with rage. Although it sounds innocent enough – putting legal doctrines, personalities and ideas in historical context – the conclusion is less ‘thought you’d like to know’ than ‘this matters’. Contextual histories aim volleys at the field’s commanding heights to change how we imagine international law and the world around us. International law’s history is not as you were taught, international law not what you thought. And the world is not the one you are accustomed to inhabiting. If we think the world is different, perhaps it will be.