This paper examines the features and practices of military command during a war of conquest, as exhibited by Castilian captains at the dawn of Iberian Atlantic expansion between the Late Middle Ages and the Early Modern Age. Focusing on Castilian royal chronicles of military campaigns against the aboriginal people of the Canary Islands, such texts demonstrate continuities with the military discourse developed during the war against the Muslims in medieval Spain, as well as adaptation to a new geographical, social and cultural context, embodied in the experiences of the conquest of the Americas. [ABSTRACT FROM AUTHOR]