Spanish fortifications in America

The coastal 'fortifications' of Spain in America are the works of military engineering that bear witness to the four hundred years of Spanish presence in America. They were built from northern California to Tierra del Fuego. Their purpose was the defense of port towns against the attack of the fleets of the English, French and Dutch armies, as well as corsairs and pirates.
Defense fortifications were present from the beginning of the conquest of America, military actions and diplomatic efforts that resulted in Spain's control of a vast territory. In addition to walling the populations, castles were built in the highest part, which allowed the control of the territory and allowed an effective defense.
From the reign of Felipe II onwards, notable efforts were made to build new fortifications or expand existing ones in the face of the annexationist threat from other European nations.
By 1550 certain strategic ports had become fortified enclaves: Santo Domingo, Hispaniola, and San Juan, Puerto Rico (centers of Spanish power in the Caribbean islands); Cartagena (guardian of northern South America and incursions through the Isthmus of Panama area); Nombre de Dios and later Portobelo on the isthmus; San Juan de Ulúa in Veracruz (key point and entrance to Mexico); and Havana (strategic center and meeting point for groups of ships to undertake their return voyage to Spain). Other secondary fortifications were also built in Yucatán, Florida, Central America, Venezuela and the islands to discourage attackers and foreign settlers. The first defenses were simple earthen forts armed with a few culverins and small-caliber cannons. But the capture of Havana by French attackers in 1555 highlighted the need for larger and more resistant fortifications and forts. By the end of the 16th century and during the 17th century, beginning with Sir Francis Drake's circumnavigation in (1577–1580), English, French, Dutch and buccaneer raiders ravaged Spanish trade and ports along the Pacific coasts and forced the Spanish to fortify El Callao, Panama, Acapulco, and other settlements and ports.
In the Caribbean and the Gulf of Mexico, the construction of colossal constructions designed by Spanish and Italian military engineers incorporated revolutionary architectural changes derived from advances in Europe. In 1563 the engineer Francisco Calona began redesigning Havana's fortifications to incorporate modern bastions, cannon platforms, thick-walled vaults, and a dry moat. These improvements provided the defenders with a very good firing range against attackers while providing protection against cannon attacks by the assaulting forces. The capture of the fortress of San Juan de Ulúa and the city of Veracruz (1568) by John Hawkins, and Drake's series of attacks through the Caribbean between 1585 and 1586, during which he captured Santo Domingo and Cartagena, prompted Philip II to send the renowned Italian engineer Juan Bautista Antonelli to design modern fortifications at San Juan de Ulúa and evaluate the Caribbean defenses. Antonelli's proposals led to the construction of a costly but quite effective system of fortifications that in the case of Havana resisted attempts to capture it for almost 200 years until 1762. Indeed, further attacks by Drake and Hawkins in 1595 against the improved fortifications failed at San Juan, Puerto Rico, and at Cartagena, yellow fever, malaria and dysentery, and other tropical diseases forced the attacking troops to desist in their attempts. Drake attacked and razed Nombre de Dios on the isthmus, after which the town was abandoned and activity was concentrated in Portobelo.
After the signing of the Treaty of London in 1604, European competitors occupied the vacant territories in America, which became excellent stalking points from which to launch more planned and larger attacks. Simultaneously small forces of buccaneers, often supported by European allies, plundered and ravaged the ports. They massacred the Portobelo barracks in 1668 and managed to capture numerous Spanish coastal towns and fortifications. On several occasions, buccaneers forces crossed the isthmus, capturing Spanish ships, and captured weakly fortified Pacific ports in Central America, Mexico, and Peru. While the great fortresses of the Caribbean should have been impregnable against such attacks, problems with the availability of troops in barracks and difficulties in maintaining large-scale works, artillery, and stores provided opportunities for surprise lightning attacks.
As revenues declined during the 17th century, poorly recruited and trained Spanish troops in the Americas lacked the determination to defend the fortifications against buccaneer attack. Campeche fell in 1672, and in 1683 a buccaneer force stormed the Fortress of San Juan de Ulúa and captured Veracruz. They sacked the town, killed 300 of its 6,000 inhabitants, and even threatened to massacre the entire population if a ransom was not paid. With the arrival of the annual Spanish fleet, Mexican military forces from Puebla, Orizaba, Jalapa, and Cordoba reoccupied the town and found destroyed buildings and the bodies of people and animals rotting in the streets. As a consequence of this disaster, Mexican authorities organized special tribunals to investigate and punish military personnel who had not defended the fortifications effectively.
During the wars against Great Britain in the late 18th and early 19th centuries, Spanish forces and fortifications helped resist and repel British attacks on Cartagena de Indias (1741), La Guaira [1743], Puerto Cabello (1743), San Juan de Puerto Rico (1797), and discourage plans to invade Mexico in the period 1805 to 1807. Although the fortress of San Juan de Ulúa was the last bastion of Spanish power in Mexico until 1825, it did not serve the Spaniards to reconquer the viceroyalty. Throughout the 19th century, many of the fortifications were converted into prisons and penitentiaries, rather than serving as sentries to protect strategic ports against foreign advances.