PRESIDIOS. When the Spanish frontier expanded northward from central Mexico, the presidio, the mission, and the civil settlement became related frontier institutions for supporting Spanish colonization. Spanish missions generally were accompanied by presidios. Martín Enríquez, fourth viceroy of New Spain (1568–80), is generally credited with originating the presidios of the Southwest. He ordered the construction along the main road from Mexico City north to Zacatecas of casas fuertes (“fortified houses”). Eventually the name was changed to presidio (from Latin praesidium, “garrisoned place”). The pattern of the early presidios was learned from the Moors and dated from the days of the reconquest in Spain. By the early eighteenth century, when Spaniards settled Texas, it had changed but little.
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