Several factors contributed to the integration of the modern pentathlon in the Olympic program in 1912 with Swedish and French voices playing a significant role. This paper focuses specifically on the French impact on the modern pentathlon with a twofold approach, which explores both the preparation and the staging of the first modern Olympic pentathlon in Stockholm between 1909 and 1912. It is primarily based on French and international sources from the Comité national olympique et sportif français (CNOSF), including documents of the Fédération française de pentathlon moderne (FFPM), the Bibliothèque nationale de France (BnF), the IOC Olympic studies centres (OSC) in Lausanne and the Riksarkivet (national archives) of Sweden in Stockholm. France appears to have played a dominant role in the early hours of the modern pentathlon. This role was, however, undermined by Swedish sports and organizational successes.