The early Republican period in Chinese history witnessed the emergence of a new generation of academic professionals. These new professional historians criticized the centrality of ancient historical time in Chinese historical studies. In contrast, they embraced objectivity as a goal of historical practice and regarded intellectual autonomy as integral to the discipline. With the shift in focus of historical studies, in the 1920s, some new academic professionals carved out a niche for themselves by developing world history into a specific teaching field. By the early 1930s, world historians such as Lei Haizong dedicated themselves to placing China’s past and future within a world-historical context. This chapter contends that the pursuit of intellectual autonomy was, however, interrupted by the war with Japan. At this moment of crisis, world historians exemplified by Lei Haizong became increasingly nationalistic. These historians glorified the unique nature of Chinese culture to promote national identity at a moment of crisis. As a result, a binary opposition between China and the world gradually emerged in Chinese historiography.