Archduchess Mariana of Austria was born in 1634, daughter of Maria Anna of Spain and Ferdinand III, Holy Roman Emperor. As a child she enjoyed a full and rounded education in her father’s court.
Aged 11, Mariana was betrothed to Balthasar Carlos, Prince of Asturias, and son of King Philip IV of Spain. However, Mariana and Carlos’ engagement ended just a few months after it began when the Spanish heir unexpectedly passed away in October 1646.
By January of the following year, Mariana was once again betrothed, this time to the recently widowed King Philip IV of Spain.
Philip IV was not only the father of the late Carlos, but was thirty years Mariana’s senior, and her biological uncle. In spite of this, the royal couple were wed in 1649.
Mariana went on to give birth to five children, but only the youngest, Charles II, survived to adulthood. Though he survived, Charles was plagued by ill health due to centuries of inbreeding within the Habsburg dynasty.
In 1665, when Philip IV died, Charles was just 3 years old, so Mariana assumed the regency of Spain – a position she held until 1675 when Charles turned 14.
Despite her best efforts, Mariana ceded power to her rival John of Austrian the Younger, Charles’ illegitimate half-brother in 1677. During his regency, Mariana fled Madrid only returning 2 years later upon John’s death.
When she returned, her son married but when his wife died 10 years later in mysterious circumstances Mariana was accused of poisoning her. Charles did remarry but his second wife and Mariana never saw eye-to-eye.
Mariana died in 1696, aged 61.
Christopher Storrs, The Resilience of the Spanish Monarchy 1665-1700 (Oxford: Oxford University Press, 2006)
Grace E. Coolidge, Guardianship, Gender, and the Nobility in Early Modern Spain (Aldershot: Ashgate, 2010)
Silvia Z. Mitchell, Queen, Mother, & Stateswoman: Mariana of Austria and the Government of Spain (Pennsylvania: The Pennsylvania State University Press, 2019).