In 1669, Spain’s Queen Regent Mariana de Austria (Mariana of Austria) approved the construction of a masonry fort to protect St. Augustine. Today, we know this fortification as the Castillo de San Marcos National Monument. Yet, what do we know about the historical leader behind the monumental decision?
Born on December 24, 1634, Mariana started her life as Maria Anna in Vienna. She was the second daughter of Ferdinand and Maria Anna, the rulers of Hungary and Bohemia. Her family belonged to the House of Habsburgs, one of the most powerful dynasties in Europe. At the age of two, her father became the head of the Holy Roman Empire. Destined for a premier marriage match, she received an education in languages, history, geography, religion, and the arts.
By the age of 12, Maria Anna became engaged to her cousin, the Spanish heir. The engagement did not last as the infante passed away three months later. Instead, her widowed uncle, King Philip IV, at the age of 44-years-old married her on October 7, 1649. Upon becoming the queen consort, she adopted the Spanish name Mariana.
When King Philip IV died in 1665, he left behind Mariana and their two children – Margarita Teresa and Carlos II (Charles II). The Council of Castile appointed Mariana as queen regent until her three-year-old son came of age. Her regency inherited a bankrupt, global empire with increasing political and natural issues. During her decade of power, her contemporaries challenged her ability to govern as both a foreigner and a woman – often leading to costly wars and courtly intrigues.
Of her many decisions as monarch, several saved a faltering St. Augustine. After experiencing years of financial strain, a pirate attack in June 1668 roused Mariana to action. On March 11, 1669, the queen regent issued her decree ordering the viceroy of New Spain to send subsidies to the city. She also added funding for the building of a masonry fortification and additional soldiers. To oversee the project, she sent Don Manuel de Cendoya to St. Augustine as the new royal governor. Her judgement protected and spurred the city’s growth over the following decades. This growth even led to a later governor requesting the same regent queen for a new two-story, coquina Governor’s House in St. Augustine.
Back in Europe, an opposition grew against Mariana. Juan José de Austria (John Joseph of Austria), Philip IV’s illegitimate son, headed a military uprising in 1669 and again in 1677. The second successful coup resulted in Mariana’s exile from court. Yet, the queen regent returned once more to rule on behalf of her sickly son in 1679. Queen Regent Mariana of Austria reigned until her death on May 16, 1696 – a year after the completion of the Castillo de San Marcos.
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