Coastal fortifications of colonial Chile

In Colonial times the Spanish Empire diverted significant resources to fortify the Chilean coast as consequence of Dutch and English raids. During the 16th century the Spanish strategy was to complement the fortification work in its Caribbean ports with forts in the Strait of Magellan. As attempts at settling and fortifying the Strait of Magellan were abandoned the Spanish began to fortify the Captaincy General of Chile and other parts of the west coast of the Americas. The coastal fortifications and defense system was at its maximum during the mid-18th century.

In 1578 Francis Drake inaugurated an era of privateering and piracy along the coasts of Chile. Responding to this threat the viceroy of Peru sent in 1579 an expedition commanded by Pedro Sarmiento de Gamboa to the Strait of Magellan in order to explore the feasibility of fortifying it and by virtue of that controlling the entrance to the Pacific Ocean from the Atlantic. After surveying the strait Sarmiento departed to Spain and obtained there through the king ships and settlers for a definitive colonization and fortifying project.Duke of Alba endorsed the project and suggested some modifications. The plan included the building one fort on each side of Primera Angostura, a sound within the strait. The expedition that sailed from Spain included about 350 settlers and 400 soldiers. Back in the Strait of Magellan Sarmiento founded the cities of Nombre de Jesús and Ciudad del Rey Don Felipe during 1584. Nombre de Jesús was abandoned after only five month of existence and its population sought themselves to Ciudad del Rey Don Felipe. There, realizing there were not enough food for all, Andrés de Biedma ordered the people to scatter along the northern coast of the strait and wait for any vessel that could provide aid. Sarmiento's resupply expedition did never arrive to the straits due to a storm and only a few settlers survived to be rescued by other navigators.

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