Between 1491 and 1589, three abbesses from the House of Bourbon-Vendôme reformed Fontevraud’s extensive monastic network and made the order a Gallican bastion during the French Wars of Religion. The reform effectively centralized Fontevraud’s administration, significantly expanded abbatial power, and established the Bourbon-Vendômes as the sole patrons of the vast network. During the Wars of Religion, the Fontevrist network became a geopolitical asset, as many of the order’s houses were located in regions where the new faith was strong. This article shows how Fontevraud’s Bourbon-Vendôme abbesses used the order’s reform to lead both the monastic network and their own family to unprecedented political power and discusses their pivotal role in maintaining Gallican agency in Protestant regions.