During the 1800s Spanish colonial authorities increasingly relied on locally recruited units to provide defense for their possessions. However, Spain’s lack of interest in its Puerto Rican colony was reflected in the support given to the garrisons. Pay and supplies could be sporadic and tours of duty were extended without notice. Conditions became so bad that in 1855 a mutiny broke out among the artillerymen in San Cristóbal, who turned their cannons on the city.
With the Civil War in Spain and a smouldering rebellion in Cuba, Spain neglected Puerto Rico’s defences for much of the 1800s. The loss of Spain’s mainland colonies reduced San Juan’s strategic importance and technological advances in artillery rendered its fortifications obsolete. However, military planners in the United States looked upon Puerto Rico as a possible base to extend American influence throughout the Caribbean. They were interested in the island’s strategic location. As Alfred Thayer Mahan, a leading naval strategist, wrote, “…it would be very difficult for a transatlantic state to maintain operations in the western Caribbean with a United States fleet based upon Puerto Rico and adjacent islands”.
As tensions grew with the United States during the late 1800s, Spanish authorities updated San Cristóbal’s defences and the Ordoñez 150mm rifled cannon became the most modern gun used to guard San Juan’s harbour. New cannon were added to the city’s fortifications but, being too large for the old casemates, they were mounted on top of the ramparts and new magazines for the ammunition were improvised out of sandbags.
American support for Cuban revolutionaries eventually led to direct confrontation with Spain. The resulting war between the United States and Spain led not only to Cuban independence, but also American occupation of Puerto Rico, Guam and the Philippines and the emergence of the United States as an important military power in the Caribbean.
When the war with the United States broke out in April 1898, San Cristóbal’s cannons had not fired in anger for over a century. On the 10th of May 1898, the fortification’s batteries opened fire on the USS Yale, which was attempting to blockade the San Juan harbour. This marked the opening shots of the Spanish-American War in Puerto Rico. Two days later, a squadron of American warships arrived off the coast of San Juan and, without warning, opened fire on the city. The U.S. ships and Spanish shore batteries exchanged fire for over three hours, however the Spanish artillery could do little damage to the American ships. Even the new Ordoñez cannon were difficult to train on moving targets and slow to load – out of some 400 rounds fired, only a handful of hits were scored.
- Information signs at Castillo San Felipe del Morro
- Information signs at Castillo de San Cristóbal