Is esprit de corps the secret engine of history? Esprit de corps has played a significant role in the cultural and political history of the last 300 years. The idea was influential and debated during the European secularisation of education in the eighteenth century, the French Revolution, the United States process of Independence and the Bonapartist Empire. It was praised by British colonialists, French sociologists and during the World Wars. It was also instrumental in the rise of administrative nation-states and the triumph of corporate capitalism. Today, 'esprit de corps' continues to be influential in disparate discourses. Through several historical case studies, Luis de Miranda shows how this phrase acts as a combat concept with a clear societal impact. He also reveals how interconnected, yet distinct, French, English and American modern intellectual and political thought is. In the end, this is a cautionary analysis of past and current ideologies of ultra-unified human ensembles, a recurrent historical and theoretical fabulation the author calls 'ensemblance'.