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Inquiry Question

Historical Context


Reading 1
Reading 3



Table of

Determining the Facts

Reading 2: The Evolution of a Defensive System

San Juan's first defensive building was Casa Blanca, a substantial structure used to store weapons and government funds. It also was built to house the first Spanish governor, Ponce de León; he never lived in it, but his descendants did for more than 250 years. Strategists soon began telling the king to improve the defenses: given that Puerto Rico was "the entrance and key to all the Indies ... [and] the first to meet the French and English corsairs [pirates]." They also suggested that he "should order a fort built ... or the island will be deserted." 1

The government then built what became known as La Fortaleza (the Fortress). Construction started in 1533, but because it did not have cannons or permanent troops, the building was almost useless for any military purpose. Even if it had had weapons, many observers complained, La Fortaleza was certain to be ineffective because it had no command of the harbor entrance. Gonzalo Fernández de Oviedo, a Spanish historian who saw La Fortaleza when construction began, reported that "only blind men could have chosen such a site for a fort." The fort should have been built, Oviedo suggested, on el morro, a headland at the harbor entrance that stood at the top of a steep slope 100 feet high. Within two years, the Crown approved funds to fortify el morro. Its first structure was a round masonry tower called San Felipe del Morro in honor of King Phillip II. The water battery, a semicircular platform intended to hold cannons, was later constructed over the rock at the foot of the slope below the tower.

Funds for construction came from a central government located in Mexico. Known as the vice-royalty of New Spain, it collected taxes from the richest areas and distributed them to areas like Puerto Rico that lacked their own wealth but were crucial to defending Spanish territory and shipping. These government subsidies, known as situados, continued through the 18th century, paying for land fortifications, soldiers, and armed ships.

Later events demonstrated why San Juan needed strong defenses. In 1595, Sir Francis Drake, the infamous English buccaneer, unsuccessfully challenged the entrance to the harbor in an attempt to seize a cargo of gold and silver awaiting transport to Spain. Three years later, another Englishman, the Earl of Cumberland, entered the harbor, captured the governor's headquarters, and besieged El Morro, as the fort had come to be known. An epidemic of dysentery soon forced the Earl to abandon his plans to make San Juan a permanent English station in the Caribbean.

After Cumberland withdrew, El Morro's defenses were improved again. Its hornwork (fortifications that resemble the outreaching horns of a bull, intended to cut off the possibility of a land attack) was rebuilt, and a new gun deck overlooking the harbor channel was added. In 1625, a Dutch fleet forced its way into the harbor and captured the city of San Juan. When it laid siege to El Morro from the land side, however, the defenders offered stiff resistance and drove off the Dutch.

Over the next 150 years, San Juan's defenses became more elaborate. In 1645, King Felipe IV remarked, "It is the front and vanguard of all my West Indies, and consequently the most important of them all—and the most coveted by my enemies."2 El Morro, for example, became a six-level complex that rose 150 feet above the ocean. Cannons could now cover both land and water approaches. Other work added storerooms, troop quarters, a chapel, and a prison; ramps, tunnels, and stairways offered access to the different areas of the fort.

El Morro was not the only area the Spaniards strengthened. Among the additional works was a small masonry fortification across the bay to the west of El Morro. Named San Juan de la Cruz (St. John of the Cross), it is usually called El Cañuelo after the tiny island on which it was built. A wooden stockade originally defended this site, but Dutch attackers burned it during their 1625 assault. A stone fort was built in the 1660s to help defend the harbor entrance and the mouth of the Bayamón River, which linked San Juan to inland settlements.

Another fortress developed along the coast about a mile east of El Morro. Castillo de San Cristóbal (St. Christopher Fort) is the largest fortress built by the Spanish in the Americas. Its construction in 1634 started with Fortín del Espigón, located on the northeast edge of Old San Juan. A fortified wall, much of it built with forced labor, gradually enclosed the entire town. Over the next century San Cristóbal developed into an elaborate fort. Covering about 27 acres, it defended the town from land attacks from the east. Its main section was a hornwork that essentially continues the walls surrounding the city. In front of the hornwork were three fortifications: the San Carlos and Santiago ravelins and the Trinidad counterguard; a dry moat surrounded them. Beyond the moat was a sizable plaza de armas (open area) that led out to a strong fort whose arrow-shape led it to be called El Abanico (the Fan). Seaward from El Abanico are Santa Teresa, a battery aimed at the ocean, and La Princesa, whose guns could fire towards the sea and land. The highest part of San Cristóbal was the caballero (cavalier), a large gun platform on top of the hornwork.

Many of these improvements occurred after King Charles III took the Spanish throne in 1759. He ordered three men in the Spanish army—Field Marshal Alexander O'Reilly, Chief Engineer Thomas O'Daly, and Chief Engineer Juan Francisco Mestre—to make the island a "Plaza Fuerte," or "Defense of the First Order." They modernized and expanded both Castillo de San Cristóbal and Castillo de San Felipe del Morro, thickened the city walls, and built new batteries at various places along the wall. By the end of the 1780s San Juan was one of the most heavily fortified cities in the Americas, so much so that military facilities had taken over much of the old city. These defenses proved their effectiveness in 1797, when they helped Spanish soldiers repulse 7,000 British soldiers besieging San Juan.

Questions for Reading 2

1. Locate La Fortaleza on Map 2. What were the problems with its location?

2. Why did the Spanish choose to fortify "el morro"?

3. Locate El Cañuelo and El Morro on Map 2. How could these two work together to defend the harbor entrance?

4. What kinds of changes were involved in making San Juan a "Defense of the First Order"?

Reading 2 was adapted from The Forts of Old San Juan (Washington, D.C.: U.S. Department of the Interior, National Park Service); "The Historic Fortifications of San Juan: La Fortaleza and San Juan National Historic Site" (Nomination to the World Heritage List by the United States of America, 1982); and Albert Manucy and Ricardo Torres-Reyes, Puerto Rico and the Forts of Old San Juan (Riverside, Conn.: Chatham Press, 1973).

¹Albert Manucy and Ricardo Torres-Reyes, Puerto Rico and the Forts of Old San Juan (Riverside, Conn.: Chatham Press, 1973), 29.
²Ibid., 23-4.


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