Castillo de San Marcos in St. Augustine, Florida

The conquest of the Americas began with the European discovery of the continent in the late 1400s—it didn’t take long for people to start killing each other over it. The Spanish had conquered much of South America, and they knew that the best way to sail back and forth between the New World and Europe entailed travel along the coast of Florida. This created a need to establish bases in Florida to keep enemies, both military rivals and pirates, from striking their treasure-laden ships returning to Spain full of plundered cargo from South America.

While Spain was the first to claim the Florida territory, it was the French who were the first to establish a base–Fort Caroline (1564, near present day Jacksonville). The Spanish set up shop a little farther south at a spot they named St. Augustine (1565). Soon afterwards, the French sent a fleet to wipe out the Spanish, but their ships were lost to storms. Knowing that Fort Caroline was low on men, the Spanish, under Don Pedro Menendes de Aviles, marched troops north, captured the fort, and killed everyone in sight. As a result of the demise of Fort Caroline, St. Augustine became the earliest European settlement in North America and is today the oldest city in the United States.

With the French out of the way, Spain’s newest rival for the territory became England. In 1586, the British attacked and burned St. Augustine, and by 1607 they had set up base at Jamestown in Virginia. British pirates attacked and plundered St. Augustine in 1668, and by 1670 the British had moved a little closer with the establishment of Charleston in South Carolina. It was time for the Spanish to beef up the defense of St. Augustine, and construction on what would become Castillo de San Marcos began in 1672. It took 23 years to complete—1695. Prior to this, St. Augustine had been protected by many wooden forts that had come and gone over the years. Castillo de San Marcos was the first built of stone (coquina, a sedimentary rock made from of crushed sea shell material).

Coquina

Castillo de San Marcos was originally designed as a fortress for the protection of St. Augustine’s citizens whenever the city was being bombarded by cannon fire from its enemies. It did not house soldiers. Soldiers lived in the city and did 24 hours of duty at the fort until replaced, at which time they returned home. Only during a siege was the fort occupied for long periods of time, and it was occupied by both soldiers and the civilian population of St. Augustine. Most of the rooms in the fort were therefore not barracks but storage rooms for munitions and food. Over the subsequent years the fort was remodeled and renovated by its various occupiers. It was not until the mid-1700s that the fort was remodeled to hold additional cannon at any location along the upper deck of the fort (the terreplein), allowing it to effectively defend St. Augustine instead of simply acting as a retreat. Prior to this, only the bastions (diamond shaped structures at the four corners of the fort) could support the weight of cannons.

Bastion of Castillo de San Marcos in St. Augustine, Florida

After the British burned down St. Augustine in 1702 but left the fort unscathed, the Spanish built a wall around the city. This has long since vanished, but the National Park Service reconstructed a section of the wall that runs across park property from the fort in the direction of the original city gates, which can be seen in the historic district of St. Augustine.

Reconstructed city wall of St. Augustine, Florida

St. Augustine city gates, now consumed by modern buildings

Spain remained in control of Castillo de San Marcos until 1763, at which time it was turned over to the British at the end of the French and Indian War (aka The Seven Years War). The Brits held control until the end the American Revolution (1783). Spain had fought on the side of the new “Americans” and had defeated the British in Florida. The Treaty of Paris, which ended the revolution, gave Florida back to Spain. Eventually, tensions between the United States and Spain over the borders of the Florida territory, combined with Spain’s financial troubles due to wars and revolutions in some of its other colonies, made Spain realize that Florida was nothing more than a burden, and in 1819 Spain and the United States negotiated the Adams-Onis Treaty, part of which gave Florida to the United States. The United States changed the name of Castillo de San Marcos to Fort Marion. It was then used to house Indian prisoners captured during the Second Seminole War (1835-1842). It came under Confederate control during the Civil War, and was also used in the Spanish-American War (1898). It was decommissioned in 1900 and turned into a tourist attraction until it was made a National Monument (along with Fort Matanzas) in 1924.

Tourists enjoy a visit to Castillo de San Marcos National Monument

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