The title character Don Carlos (1545–1568) had a remarkable pedigree. Like his father Philip II and grandfather Charles V, he was descended from the famous Catholic Monarchs of Spain, Ferdinand and Isabella who had sent Columbus off on his voyage of discovery, as well as from the illustrious Austrian Emperor Maximilian I. Carlos’ grandfather, Hapsburg Emperor Charles V (1500–1558), also known as Charles I of Spain by virtue of his Spanish mother and Austrian Hapsburg father, inherited an enormous empire that rivaled the domains of the ancient Roman emperors. It included not only Spain and her possessions in Central and South America but Austria and southern Germany, Naples, Sicily, Sardinia, Milan, Burgundy, and the Netherlands (referred to in the opera as “La Fiandra” or Flanders). It was in Flanders where the “heresy” of Protestantism had reared its head, only to meet with the harsh Spanish repression, including the burning of many churches and hundreds of executions.
With such a vast empire to govern, it is not surprising that Charles V eventually grew weary of managing constant wars against everyone from the French to the Turks and supported the ruthless Spanish Inquisition in his role as Defender of the Faith. At fifty-five, he abdicated the throne and retired to the monastery of St. Yuste, the site of the two scenes in the opera in which he—or his ghost—makes a mysterious appearance as a monk. He left his Austrian possessions to his brother Ferdinand and his Spanish holdings (including the Netherlands) to his son Philip II.
Philip II was gloomy, ascetic, and solitary, the type of person whom a son might easily come to hate, as Don Carlos clearly did. Philip ruled for forty-four years and married four times:
1. Maria Manuela of Portugal (his cousin), the mother of Don Carlos who never knew her since she died in childbirth.
2 Mary Tudor, Queen of England, whose death would later give Philip the claim to the English throne that would justify his famous, failed Spanish Armada in 1588.
3. Elizabeth of Valois, daughter of the king of France and Catherine of Medici. As we have seen, the opera’s plot is based on the fact that there had earlier been talk, when the two were young children, of Elizabeth’s marrying Don Carlos. They were both fourteen when Elizabeth married his father instead.
4. Archduchess Anne of Austria, his own niece, who would bear him his ultimate heir, Philip III.
You will no doubt have noticed Philip’s tendency—unfortunately shared by too many of his fellow Hapsburgs—to marry his own relatives. It shouldn’t be too surprising, then, that the real-life Don Carlos turned out to be a much more bizarre character than he is depicted to be in the opera.
He was described as pale and small of stature with one shoulder higher than the other. He had the elongated chin and jaw that were typical of the Hapsburgs. As a result, he had a speech impediment and also suffered from seizures. (He has a mild one in the opera, swooning during his Act II duet with Elizabeth.) He was prone to fits of homicidal mania. He attempted to throw a servant out a window, roasted rabbits alive, stunned the courtiers by biting the head off a lizard, and locked himself in a stable and beat twenty-three horses nearly to death. Unhappy with some new boots, he forced the shoemaker to eat them. He even once attempted to stab the Grand Inquisitor. (That would make a great scene for an opera, but Verdi already had enough material to work with.)
As depicted in the opera, Don Carlos did harbor ambitions to rule Flanders, but probably out of egotism rather than out of any concern for the injustices being done to the people there in the name of the Inquisition. Exasperated with his outlandish behavior and open rebelliousness, his father at last had him put under house arrest. Don Carlos died six months later, at the age of twenty-three, reportedly from an excess of gluttony, although rumors spread that he had been poisoned.
In contrast to its inaccurate, toned-down portrait of Don Carlos, the opera’s characterization of Elizabeth seems close to historical truth. Sources seem to agree that she was beautiful, kind, intelligent, and regal. She was as popular with the Spanish people as she had been in France. She and Don Carlos seemed to be fond of one another, but it is doubtful that there was an actual romance between them. She died of a miscarriage a few months after the death of Don Carlos.
Rodrigo or the Marquis de Posa, Don Carlo’s bosom friend in the opera, is possibly based on a real person, the Marquis de Poza, a shadowy figure in history who seems unlike his noble and self-sacrificing operatic counterpart. One story has him involved in a scandal that resulted when he was caught climbing out the window of one of Elizabeth’s maids of honor. There is no evidence that he and Don Carlos were boyhood friends. Poza’s son was reported to have been accused of heresy and burned alive in an auto-da-fé (Act of Faith), the ceremonial execution portrayed in Act III of the opera.
Much more is known about the real Princess Eboli, an heiress born Ana de Mendoza in 1540. King Philip married her off to one of his favorite courtiers, Ruy Gomez. She became the chief lady-in-waiting to Elizabeth and was the keeper of her keys, including her jewelry case, which factors importantly in Act IV of the opera. Eboli had a reputation as a temperamental busybody, and is said to have worn a patch over one eye for unknown reasons (a fencing accident has been suggested as the cause). Of her nine children, one was alleged to have been fathered by the king. After her husband’s death, she entered a convent but quarreled with the abbess. Back at court, she entered into a liaison with one of the king’s ministers, which ended badly when he was arrested for treason. He escaped, while Eboli was first banished and later imprisoned in her own house where she died. Her real life, like that of other central characters in Don Carlo, was truly operatic.