On November 1st, 1700, the physicians of the Spanish court opened the body of their dead king and recoiled. For nearly four decades, Charles II had ruled the greatest empire on earth from a body that had been failing him since the moment of his birth. Now, with his corpse laid out on the dissection table, they finally saw why. His body contained not a single drop of blood.

His heart was shriveled, blackened, barely recognizable. His lungs were corroded, scarred so badly they looked more like pumice stone than organs meant for breathing. His intestines were rotten, gangrenous, parts of his digestive system having died while he was still alive. His brain, for which they had always suspected the worst, was full of water, the fluid leaving barely any room for actual brain tissue.

And then there was the detail that confirmed everything they had whispered for years: Charles had only one testicle, and it was black as coal. How this collection of malformed organs had sustained life for nearly four decades was a medical mystery. But the answer had been written into his blood decades before he drew his first breath. To understand how a king could be born so broken that his own mother recoiled in horror, you have to go back nearly two hundred years, to when the House of Habsburg discovered what they believed was the secret to eternal power.

Their motto became a warning disguised as wisdom: “Let others wage war. You, happy Austria, marry. ” They meant each other. For almost two centuries, the Spanish branch of the Habsburg dynasty had been marrying cousins, uncles marrying nieces, double first cousins uniting in matrimony.

They called it maintaining the purity of blood. Over eighty percent of Spanish Habsburg marriages were between close relatives. Not distant cousins met once at a family reunion, but people who shared grandparents or, in some cases, parents. By the time Charles was born, all eight of his great-grandparents descended from the same couple: Philip I and Joanna of Castile.

Every single one. Nowhere was the cost of that “purity” more visible than in the body of the infant delivered on November 6th, 1661, in a dimly lit chamber of the Royal Palace of Madrid. The baby’s head was grotesquely large. His breathing was labored.

The midwives who delivered the heir to the Spanish throne knew immediately that something was terribly wrong. His own mother, Queen Mariana, reportedly shuddered at the sight of him and refused to nurse him. It was not maternal cruelty but something more primitive: instinctive horror. For Mariana was not just Charles’s mother.

She was also his cousin and his aunt. His father, Philip IV, had married his own niece. The family tree was not a tree at all. It was a circle.

Baby Charles could not suckle properly. His mouth was already showing signs of deformity. His skull bones had not fused as they should, leaving his head misshapen and swollen. The court physicians noted he had a weak suck and struggled to feed.

The wet nurses hired for him reported something even more disturbing: the infant rarely cried. Not because he was content, but because he seemed to lack the energy. He lay pale and still, his oversized head lolling to one side, his breathing shallow and raspy. The best physicians in Spain had never seen an infant so fundamentally broken.

As the months turned to years, the full extent of his condition revealed itself. At age four, Charles still could not walk. Not would not, but could not. His legs were thin as sticks, bowed from rickets, unable to support even his small body weight.

Servants carried him everywhere in specially designed chairs. At age four, he also could not speak. Not a single word. His tongue was already growing abnormally, filling his mouth.

His jaw, the infamous Habsburg jaw, was already protruding. When he finally spoke his first words sometime after his fourth birthday, they were slurred, wet, comprehensible to no one. The court chroniclers delicately noted that his majesty’s speech required interpretation. The interpretation was needed because of the way his face had formed.

Charles’s tongue was so enlarged it constantly protruded from his mouth. His lower jaw jutted out so severely that his lips could not close. When he tried to speak, saliva poured from his mouth. Royal attendants stood ready with silk cloths to constantly wipe the drool from the chin of the boy who would be king.

The Habsburg jaw was a condition that had plagued the dynasty for generations, but in Charles it reached its most extreme form. Imagine a normal human skull, then pull the lower jaw forward several inches without the upper jaw growing to match. The result is a mouth that can never fully close, teeth that can never meet, a tongue with nowhere to rest. In portraits, the court painters tried to minimize it, painting Charles with his mouth slightly open as if caught mid-word.

In reality, his mouth was always open because it could not physically close. Foreign ambassadors meeting the young prince for the first time struggled to maintain their composure. One French diplomat’s private letters described the shock: “The prince’s appearance defies description. His jaw protrudes so far that he appears to have two faces, one stacked in front of the other.

When he attempts to eat, food falls from his mouth. When he speaks, one must stand back to avoid the spray. ”

Eating was its own ordeal. Charles could not chew.

His upper and lower teeth were separated by such a gap that they never met. Every meal of his entire life was a struggle. Court dining became an exercise in creative cuisine. Meats had to be cut into tiny pieces, vegetables pureed, bread soaked in wine until it dissolved.

The English ambassador, Alexander Stanhope, wrote one of the most visceral descriptions: “His Catholic majesty swallows all he eats whole, for his nether jaw stands so much out that his two rows of teeth cannot meet. To compensate which, he has a prodigious stomach and swallows a whole lamb at two meals. ”

But physical deformity was only the beginning. As Charles grew, or rather failed to grow properly, other problems emerged.

He was plagued by constant illness. Measles nearly killed him at age six. Then came chickenpox, which left him covered in scars. Then rubella, then smallpox.

His compromised immune system offered little resistance to any disease that swept through the palace. The smallpox was particularly cruel. It struck when Charles was nine, and for weeks he lay between life and death. When he finally recovered, the scars joined the catalog of his disfigurements, and something worse remained.

The physicians noticed fluid building up in his skull. His already large head began to swell further. Today it is called hydrocephalus, water on the brain. In the seventeenth century, the court called it another curse upon the prince.

The pressure caused blinding headaches, vision problems, and likely contributed to the seizures that would plague his later years. By age ten, Charles’s education was a source of palace scandal. Not because he was rebellious or lazy, but because he simply could not learn. Tutors reported that lessons had to be repeated dozens of times.

Basic mathematics was beyond him. Latin, the language of royalty and diplomacy, might as well have been ancient Egyptian. His handwriting, on the rare occasions he attempted it, looked like the scrawl of a much younger child. One tutor’s private notes, discovered centuries later, paint a heartbreaking picture: “His majesty tries with great effort, but retains nothing.

I explain a concept, and by the next day, it is as if he has never heard it. His attention wanders. Sometimes he stares at nothing for long periods. When asked what he is thinking, he cannot say.

”

Then came puberty. Or rather, what should have been puberty. Charles grew, but barely. While other royal teenagers shot up in height, he remained stunted.

His voice stayed high and thin instead of deepening. He developed almost no body hair. The characteristics that marked a boy becoming a man simply did not happen. The court physicians conferred in hushed conferences, discussing what they observed but dared not put into official records.

The prince showed no interest in women, nor in men, it seemed. He existed in a strange childlike state, neither boy nor man, but something in between. This terrified the court, because Charles had one job above all others: to produce an heir. The entire Spanish Empire, stretching from Europe to the Americas to the Philippines, needed the royal bloodline to continue.

But how could a man who could not grow a proper beard father children? At age eighteen, they decided to find out. Charles was married to Marie Louise of Orléans, a seventeen-year-old French princess who was by all accounts beautiful, intelligent, and healthy. The contrast between bride and groom shocked the wedding guests.

She was radiant. He was ghastly. She walked gracefully down the aisle. He shuffled, supported by attendants.

When it came time for the kiss, observers noted that Marie Louise had to steel herself visibly before leaning in. The wedding night was a disaster of the kind that determines the fate of empires. Charles was completely incapable of consummating the marriage. Not unwilling, but incapable.

His body simply did not function as a man’s should. Marie Louise, raised in the sophisticated French court, tried everything. She was patient, she was kind, she even attempted, according to palace gossip, to instruct her husband in the basics of marital relations. Nothing worked.

Years passed. No pregnancy. The queen underwent humiliating examinations to determine if she was the problem. The physicians declared her perfectly fertile.

The problem, everyone knew but no one would say officially, was the king. The pressure was crushing. Charles and Marie Louise were subjected to increasingly desperate fertility treatments. She was forced to drink vile concoctions of herbs and animal organs.

He was given potions that included ground pearls and bull’s blood. At one point, the court brought in a specialist who prescribed eating the dried penis of a stag. Nothing worked, because nothing could work. Charles’s reproductive system was as malformed as the rest of him.

Then the story took an even more bizarre turn. Charles’s mother, desperate for a grandchild to continue the Habsburg line, consulted mystics and holy men. One suggested the king was cursed and that sleeping next to holy relics might break the spell. When that failed, she escalated to something that still shocks historians: she had her son sleep next to corpses.

The Queen Mother arranged for Charles to spend nights lying beside exhumed bodies of saints and former kings, including his own father. The theory was that the holy essence of the dead would cure his impotence. Picture it: the king of Spain, drooling and malformed, lying beside decomposing corpses in the hope of gaining the ability to father a child. Ten years of marriage.

Ten years of failed attempts. Ten years of humiliation. Then Marie Louise died suddenly at age twenty-six. The official cause was listed as appendicitis, but rumors swirled.

Had she been poisoned? Had the strain driven her to suicide? The truth was never established. What is known is that Charles was genuinely devastated.

Despite everything, he had grown to love his wife, perhaps the only person who had shown him real kindness. Within months, the pressure to remarry returned. The council selected Maria Anna of Neuburg, a German princess from a famously fertile family. Her parents had produced seventeen children.

Surely, the advisers reasoned, such robust genes could overcome even Charles’s deficiencies. They were wrong. Maria Anna, despite her healthy lineage, never became pregnant. Not once.

By this time, Charles’s health had deteriorated further. Courtiers whispered that he looked like an old man, though he was barely thirty. His hair fell out in patches. His teeth, what few could be seen behind that protruding jaw, rotted and fell out.

He shuffled when he walked, when he could walk at all. The seizures began in his thirties. Without warning, Charles would collapse, his body convulsing, foam mixing with the ever-present drool. When he recovered, he often did not recognize the people around him.

He began talking about seeing ghosts, hearing voices, feeling invisible hands touching him. The court was terrified. Was their king going mad on top of everything else? His nickname had long been El Hechizado, the Bewitched.

Now it took on new meaning. People genuinely believed Charles was under a curse. The Spanish Inquisition became involved. Exorcists were brought in.

At one point, the king’s own confessor was arrested on charges of using witchcraft to worsen the royal condition. The trial was a sensation. No amount of exorcism could cure genetic damage, of course, but Charles himself believed he was cursed. In his lucid moments, he wept and asked what he had done to deserve such punishment.

He wore amulets, carried holy relics, submitted to increasingly bizarre purification rituals. Nothing helped, because nothing could help. His genetic code was the curse, written into every cell of his body. By age thirty-five, Charles looked ancient.

Contemporary descriptions are hard to read. His skin hung loose on his skeletal frame. His jaw seemed to grow even more pronounced as the rest of his face wasted away. He was completely bald, his scalp covered in sores.

He could barely walk, shuffling a few steps before needing to rest. His speech, always difficult, became nearly impossible to understand. In his final years, Charles’s mind deteriorated rapidly. He sat for hours staring at nothing, drool pooling on his clothes.

When spoken to, he often did not respond. When he did speak, he rambled about demons and angels, about his dead wife, about the children he would never have. The king of one of the world’s greatest empires had become a hollow shell. The end came in 1700.

Charles was thirty-eight years old, not elderly by any standard, but his body was shutting down. He could not eat even his specially prepared mush. He could not stand without help. He spent his days propped up in bed, gasping for breath, the pressure in his hydrocephalic head causing unbearable pain.

On November 1st, after days of agony, Charles II died. The autopsy that followed revealed the full extent of the damage, and modern genetic analysis has provided the explanation behind it. Charles’s inbreeding coefficient, the percentage of his genes that were identical copies from common ancestors, has been calculated at 0. 254.

To put that in perspective, a child of brother-sister incest has a coefficient of 0. 25. Charles II was more inbred than a child of siblings. Scientists now believe he suffered from at least two major genetic disorders.

The first was combined pituitary hormone deficiency. His body could not produce the hormones needed for normal growth and development. This explained his short stature, his failure to sexually mature, his muscle weakness, his cognitive problems. His pituitary gland, the master controller of the endocrine system, was essentially non-functional.

The second was likely distal renal tubular acidosis. His kidneys could not properly regulate his blood chemistry, causing the rickets that bent his legs, the muscle weakness that left him unable to walk, and possibly contributing to the hydrocephalus that swelled his skull. Either condition alone would have been challenging; together they created a cascade of failures throughout his body. Add the Habsburg jaw itself, a genetic condition called mandibular prognathism, and the result was a perfect storm of genetic disasters.

Some researchers have proposed an even rarer possibility: aspartylglucosaminuria, a lysosomal storage disease in which patients develop normally for their first few years, then begin showing delays, and by adulthood have coarse facial features, intellectual disability, and shortened lifespans. The match with Charles’s symptoms is eerily exact. But Charles was not uniquely unlucky. He was the inevitable result of systematic inbreeding.

Of the thirty-four children born to Spanish Habsburg monarchs, more than half died before age ten. The dynasty was literally breeding itself to death, and Charles was the final, most extreme example. When Charles died without an heir, it triggered the War of the Spanish Succession, a conflict that reshaped Europe. The Spanish Empire built over centuries shattered because one man’s body was too broken to produce a single child.

The Habsburg line that had ruled Spain for nearly two hundred years ended not with an assassination or a revolution, but with a king so inbred his own flesh betrayed him. The Bourbon dynasty that replaced the Habsburgs learned the lesson. While royal marriages remained political, the extreme inbreeding that created Charles II was never repeated. The nightmare of the Habsburg jaw, the horror of the autopsy, the tragedy of a king who could not chew his own food: these became cautionary tales whispered in royal courts across Europe.

Charles II remains in medical textbooks as the ultimate example of genetic collapse. Students of genetics see his portrait and learn about inbreeding coefficients. His Habsburg jaw has become shorthand for the dangers of closed gene pools. In a strange way, his suffering contributed to our understanding of heredity and the importance of genetic diversity.

But beyond the medical curiosity, beyond the political consequences, there was a human being. Charles II lived every day in a body that was failing him. He endured constant pain, humiliation, and the knowledge that he was failing in his most basic duty as king. He was mocked as the Bewitched when his only curse was his ancestry.

In his final letter, dictated because he could no longer hold a pen, Charles wrote of hoping to find in death the peace that had eluded him in life. The portrait hangs now in the Museo del Prado in Madrid. Visitors pause before it, struck by the obvious deformities even the court painter could not fully hide. Charles II of Spain was not cursed by witches or demons.

He was cursed by his own family tree, a tree so tangled it had become a noose. In trying to keep power in the family, the Habsburgs destroyed their own bloodline. Behind the crowns and scepters and royal grandeur, biology always has the final say.