Keywords: Medieval History, Medieval merchants, Argumentation, Francesco Datini. Parole chiave:
Argumentation in business settings has gained renewed interest within social science research. Managers are seen as rhetors, and the spread of a practice depends on the discursive justifications used to rationalize it. These topics are particularly relevant for understanding the business leadership of one of the most famous merchants of the late Middle Ages: Francesco Datini, «The Merchant of Prato.» The merchant rhetor’s persuasive effort was practiced daily through his letters (not theorized) and became a cornerstone for building both a strong holding company and a trusted relationship with his partners. This case study provides a contribution to the history of Middle Ages merchants’ culture and to the impact of language in business activities.