While cultural entrepreneurship research has highlighted how entrepreneurs craft stories to legitimize their ventures, we know much less about how entrepreneurs gain legitimacy for a novel organizational form. Drawing upon a detailed, historical examination of Japanese family mottos from the Edo period (1603–1868), we show how stories embedded in family mottos enabled legitimation by symbolically leveraging two core socio-cultural institutions of Edo Japan (religion and family), advancing our understanding of how broader cultural resources can be leveraged to legitimate a new organizational form. We discuss implications for scholarship on family business and cultural entrepreneurship.