Few generalizations in Spanish historical thought command readier assent than that which affirms the profound influence of the Reconquest on the making of Castile. Yet it is only in recent decades that scholars like Claudio Sánchez-Albornoz, J. M. Lacarra, Julio González, and others have established the thesis that those eight centuries of now slow, now rapid southward advance against the Moors were not merely an Iliad of military and political combat, but above everything else a medieval repoblación, or recolonization, of the Iberian Peninsula. 1 From this standpoint, the Reconquest appears as a frontier movement in the authentic American sense—the occupation and development of relatively empty territories on the margin of an expanding society.