The iconic image of the knight on horseback represents just one facet of the horse’s imprint on legal, political, and social systems developing in medieval Iberian society. This chapter argues that historical and bodily relations with horses shaped the negotiation of social status and the administration of territory during the dynamic periods of peace, conflict, and negotiation among Iberian kingdoms in the tenth to fifteenth centuries. Defining the set of practices, ideals, and institutional hierarchies making up an Iberian "culture of the horse” brings to light a fundamental tension in which the horse served as both an agent of control and a means to disrupt power relations.

Although Spanish colonizers expected horses to enforce social order, new environments for breeding and keeping horses and colonial interdependence on Indigenous populations also subverted these expectations. Licenses to ride horses offers a widespread example of this new political ecology. Across New Spain and Peru, Indigenous allies gained access to horses according to Spanish customs that rewarded military service to the crown, cases that emphasize the powerful imprint of the horse in Spanish governance. More broadly, the development of Indigenous equestrianisms both within and outside of Spanish spheres of influence demonstrate the complex boundary work involved in navigating a new interspecies landscape and producing new forms of knowledge.