Bulletins et Mémoires de la Société d' Anthropologie de ParisCet article fait suite à une communication invitée présentée lors des 1847 es journées de la Société d'Anthropologie de Paris dans le cadre de la session "Les relations entre les humains et les animaux"Abstract -The findings of Librado et al. (2021) show that modern domestic horses (DOM2) emerged in the lower Don-Volga region. They imply that horseback riding drove selection that resulted in these horses and fuelled their initial dispersal, and also that DOM2 horses replaced other horses because they were more suitable for riding due to their more docile temperaments and resilient backs. In this article, I argue that captive breeding of horses leading to their domestication began in about 4500-3000 BC in the Pontic-Caspian steppe and made horseback riding necessary because managing horses, and especially moving them over long distances, required mounted herding. Horseback riding had been experimented with since the second half of the 5 th millennium BC, became common around 3100 BC during the early stages of the Yamnaya culture, and necessary by the middle of the 3 rd millennium BC at the very latest. As horseback riding became more common, selection for malleable temperaments and resilient backs intensified, resulting in DOM2 horses by about 2300-2200 BC in the lower Don-Volga region. The body size and weight-carrying ability of ancestral and early DOM2 horses were not limiting factors for horseback riding. The initial dispersal of DOM2 horses was facilitated by horseback riding and began by about 2300 +150 BC. Chariotry began to spread together with DOM2 horses after 2000 BC, but its high archaeological visibility may have inflated its importance, since chariots are of limited practical use for herding and other daily tasks.