This article explores the consequences of the Austro-Hungarian Empire's end through the tumultuous biography of a philanthropic entrepreneur and quasi-consul community leader known today for assisting thousands of Jewish refugees during World War II. Focusing on Paul Komor (1886–1973) and the migrant community of Shanghai Hungarians, the article contends that postimperial diasporas preserved a piece of empire in their commitment to Jewish emancipation, imperialist nationalism, multiple loyalties, and political nostalgia. It also argues that diasporic networks and charitable actions communicated political and national loyalties while creating and defining the boundaries of the community. Presenting original research involving sources in multiple languages from China, Hungary, the U.S., the U.K., and the Netherlands, the article traces the fortunes of a Jewish Hungarian family in colonial Shanghai, shows the limits of its son's charity-rooted advancement in community leadership, sheds light on the seemingly contradictory political ideas of a postimperial expatriate to explain his complicated relationship with his kinstate, and analyzes the institutionalization of communal charity and the competing prerequisite definitions of postimperial national belonging.