Repoblación

The Repoblación (Spanish: [repoβlaˈθjon]; Galician: [repoβo̯aˈθjoŋ]; Portuguese: Repovoação, IPA: [ʁɛpuvuɐˈsɐ̃w]) was the ninth-century repopulating of a large region between the River Duero and the Cantabrian Mountains which had been depopulated in the early years of the Reconquista.

In the reign of Alfonso I of Asturias (739-757), through a series of successful military campaigns against the Moors, the Christians had retaken Galicia, La Rioja, and León and brought the population of the northern regions firmly under their control. This left those provinces largely empty of human settlement and created a buffer zone between Moors and Christians. This region was called the Desert of the Duero. This zone was left untouched for almost a century while Alfonso's successors focused their energies on Vasconia and Galicia.

It was during the reign of Ordoño I of Asturias (850-866) that the repopulation of the uninhabited zone began. Ordoño began advancing to the south, repopulating the cities of Tui, Astorga, León, and Amaya. The people who descended the mountains of the north for the uninhabited valleys were called foramontanos: meaning "out of the mountains." Among the routes the foramontanos took was that between Cabuérniga and Campo de Suso, which was followed as early as 824, when the new population of Brañosera received the oldest known fuero in Spanish history.

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Wikipedia