The art and craft of writing history are inherently linked with international-law scholarship. Finding precedents and doctrinal authority and reading the political compromises underpinning institutions are typical purposes. Lawyers, academics and political actors have all been receptive to a historical narrative. The structure and arguments used in international law are closely linked with Western legal culture and the reception of Roman law. This setting is at the same time broader and more restrictive than that of professional academic historians, who developed theoretical standards to distinguish their thought-through production (historia rerum gestarum) from the rendering of brute facts (res gestae) or from a purely literary product. This chapter starts with German and French eighteenth-century visions of the law of nations, before passing to the nineteenth-century passion for history. The ‘men’ of 1873 (Institute of International Law) and twentieth-century evolutions led to the recent boom in scholarship. The ‘turn to history’ in international law not only continues past traditions, but also reflects broader transformations in the social sciences and humanities. Conversely, we witness a contemporary ‘turn to law’ in intellectual, political, cultural and social history, which leads to a stimulating process of cross-fertilisation.