Christopher Columbus located Puerto Rico on November 19, 1493, and named it San Juan Bautista. Fifteen years later, a member of Columbus' original party, Juan Ponce de Leon, returned with 50 soldiers and a small group of settlers. They established a small settlement on the south shore of San Juan Bay, called Caparra. It turned out to be swampy, hard to reach from the port, and hard to defend. The local Taino aborigines initially welcomed the Spanish, but when the Spanish started kidnapping Taino women and Taino people started falling from European diseases, their attitude changed. They began to fight back against the Spanish, but their primitive weapons were no match for Spanish firearms. The Spanish pressed Taino people into slave labor in their gold and silver mines. By 1519, the Taino population was down from 30,000 to fewer than 4,000. Between 1519, by order of the King of Spain, Caparra was moved to a healthier, more readily defensible site overlooking the Atlantic Ocean. The settlement continued to fight off attacks from the area aborigines, the warlike Caribe now joining the remnants of the Taino. Mining dwindled and was replaced by agriculture. African slaves were introduced. The Spanish Empire established regular trade routes throughout the Caribbean, South and Central America, further reinforcing San Juan's position as a gateway city.
It became increasingly clear to the Spanish crown that San Juan was an important port city that needed to be defended--from other countries' navies, from pirates, and from aborigines. Beginning with La Casa Blanca, a storehouse for government funds and weapons, the army at San Juan set about building an array of forts and military workings along the cliff face overlooking the harbor. These were crowned by El Morro de San Felipe, on which construction began in 1539. In 1595, it repelled an attack by the British buccaneer Sir Frances Drake. In 1598, the Earl of Cumberland unsuccessfully besieged El Morro. In 1625, a Dutch force besieged the harbor. The city was walled off, and the walls were reinforced in the 18th century. During the seventeenth and eighteenth century, more forts were built. In 1797, an attack by the British under Sir Ralph Abercromby ended when the ships were tricked into leaving after a rogativa--a religious procession of local women--made it look as though military reinforcements had arrived. El Morro and the surrounding military fortifications protected San Juan for centuries.
During the eighteenth and nineteenth centuries, support from Spain gradually tapered off, but repressive rules of commerce continued to hold sway over Puerto Rico. An active smuggling trade grew up around the Caribbean, and a wide variety of people came to Puerto Rico to stay. On Noveber 28, 1897, Spain finally granted autonomy to Puerto Rico, and Puerto Rico elected delegates to the Spanish court. In 1898, elections were held, and Puerto Rico's autonomous government took effect. Later that year, the Spanish-American War broke out, and the U.S. invaded Puerto Rico with a bombardment of San Juan.
In October 1898, the U.S. military government took over and set about modernizing and fortifying El Morro and the surrounding forts and military buildings. Gen. John Brooke became Puerto Rico's first American governor, and El Morro was renamed in his honor. In December of 1898, the Treaty of Paris ended the Spanish-American War, with Spain ceding Puerto Rico, Guam and the Philippines to the U.S. In 1900, the Foraker Law allowed Puerto Rico to have a governor and House of Delegates appointed by the U.S. president and approved by the U.S. legislature. Puerto Rico had no vote in the U.S. legislature. In 1917, the Jones Law granted U.S. citizenship, but still no vote, to Puerto Ricans. In 1947, Puerto Rico received the right to elect its own governor. In 1949, El Morro, San Cristobal, El Canuelo, the San Juan Gate and the city wall became the San Juan National Historic Site, under the administration of the National Parks Service. The site was later designated a United Nations World Heritage site.
San Juan expanded far beyond the walls, incorporating Rio Piedras, Hato Rey, Puerta de Tierra, Santurce, Condado and Miramar in the 1950s. Old San Juan now occupies about seven square blocks of residential and commercial area. It features narrow streets cobbled with original blue adoquine stones made from furnace slag that was brought over as ballast on ships. Old San Juan has more than 400 restored 16th and 17th century buildings. A full walking tour of important sites in Old San Juan takes two days.