[ES] El presente trabajo pretende aportar algunas ideas sobre el proceso de transici?n de la Antig?edad a la Edad Media y la formaci?n de la sociedad feudal en el norte peninsular. Se ha seleccionado un ?rea de la cuenca del Duero donde poder contrastar emp?ricamente la documentaci?n escrita con el registro arqueol?gico. De este modo surgen serias dudas en la teor?a tradicional de la "despoblaci?n del valle del Duero", la creaci?n del "yermo estrat?gico" y la "repoblaci?n" a cargo de campesinos libres. Por el contrario, este sector de la meseta leonesa parece haber constituido una "reserva" montaraz de las explotaciones tardorromanas ubicadas en los valles pr?ximos. La desarticulaci?n de sus estructuras de poder permitir?a al campesinado ir ocupando y poniendo en explotaci?n ese espacio, que desde el siglo X va a ir siendo objeto de progresivas apropiaciones ("presuras", "populationes"...) por parte de los nuevos se?ores vinculados a la monarqu?a asturleonesa: monasterios, magnates y familia regia. La supuesta "repoblaci?n" no es, por tanto, sino la apropiaci?n feudal de las explotaciones campesinas preexistentes.

[EN] This work offers new ideas on the transition process from the Late Antiquity to the Early Middle Ages and the origin of the feudal society in the north of the Iberian Peninsula. An area was selected where the written documentation could be proved with archeological research. Thus serious doubt is cast on the traditional theory of the "depopulation of the Duero Valley", the creation of a "strategic desert" and its repopulation by independent peasants. On the contrary, this region would have been a restricted wooded area belonging to the landlords of the Late Roman Villas located in the vicinity. With the breakdown of the power structures of Late Roman, peasants would have occupied and exploited these lands. Later, in the tenth century, according to written documents, these areas and farm were progressively taken over by the new aristocracy: monasteries, nobility and the royal family of the Astur-Leonese Kingdom. The supposed repopulation would therefore have actually been a feudal conquest of properties previously belonging to peasants.