The glass king: how Charles VI of France lost his mind

In the late 14th century, France was one of the most powerful kingdoms in Europe. However, beneath the polished veneer of Valois pageantry, a slow-motion catastrophe was unfolding, one marked by mental illness, factional civil war, foreign invasion, and a queen whose legacy has been fiercely contested ever since.

At the centre of this story are Charles VI, a king afflicted by episodes of terrifying madness, and Isabeau of Bavaria, a queen consort who found herself navigating an impossible political landscape. Their reign was one of the most chaotic in the long history of the French monarchy. Buckle up because it’s a wild ride…

From “beloved” to “mad”

Charles inherited the French throne in 1380, when he was just 11. While he was still a child, his power-hungry uncles - the Dukes of Bourbon, Berry, Burgundy, and Anjou - ran the show, while helping themselves to royal funds and influence like kids in a candy store. When Charles turned 20, he emancipated himself, stripped his corrupt uncles of their positions, and reinstated his father’s officials. Under his rule, France’s finances were slowly restored and the people, charmed by their young, reformist monarch, dubbed him “the Well-Beloved.”

In the summer of 1392, everything changed.

Medieval Europe wasn’t exactly known for its chill, and the story of Charles’s first mental breakdown fits right in with the era’s signature weirdness. It all started when a man named Pierre de Craon tried to murder one of Charles’s close friends. When he fled to Brittany and the local duke refused to hand him over, the young king set off with an army to bring him to justice.

Their expedition got off to an unsettling start. As the men journeyed through a forest in the sweltering August heat, a bedraggled leper ran up to the king shouting “Turn back, noble king! You are betrayed!". Despite being shoved aside, the man kept following the king, yelling his warning again and again.

Charles had already been acting unusually and showing signs of manic energy. So when one of the pages accidentally dropped a lance, the sound of clashing steel triggered something deep inside of the king. Taking the leper’s warning to heart, he drew his sword, shouting “Forward against the traitors! They wish to deliver me to the enemy!" and turned on his own men, deep in a delusion that they were out to get him. He killed one man and wounded several others before his companions managed to wrestle him to the ground. When he finally collapsed, he lay motionless for two days, completely unresponsive, as if in a coma. When he finally came to, he had no memory of what happened.

It was the beginning of a lifelong struggle. From that moment on, Charles experienced regular episodes of confusion, violent paranoia, memory loss, and hallucinations. On one occasion, he refused to bathe or change his clothes for months. His court was forced to find ways to accommodate his behaviour, doing things like hiding mirrors so he wouldn’t become distressed by his own reflection.

The glass king

One of the most famous and bizarre aspects of Charles’s illness was his belief that he was made out of glass. He was convinced that he would shatter into pieces if anyone bumped into him. Courtiers were forbidden to come near him and he even wore specially-designed protective clothing that was reinforced with iron rods. It’s hard to imagine how scared and confused Charles must have been - he would often sit motionless for hours, terrified that any sudden movement could make him smash like a vase.

Strange as it sounds, Charles wasn’t the only person to suffer from a ‘glass delusion’ in medieval and early modern Europe. One man was even convinced his bum was made from glass and that sitting down would make it break. Another individual travelled to the glass-making hub of Murano, where he planned to throw himself into a furnace and transform into a beautiful goblet. Earlier in history, there were cases of ‘earthenware men’. Scientists think these delusions were influenced by new technologies - clear glass was a relatively new development in Charles VI’s era - along with a fear of physical contact.

(As an aside, the man who thought he had a glass bottom was cured when his doctor spanked his ass!)

Modern doctors think it’s likely Charles suffered from paranoid schizophrenia and/or bipolar disorder but in an era without diagnosis or treatment, his symptoms remained a terrifying mystery.

One hell of a party (or the party from hell)

Charles’s doctor decided he needed some good old-fashioned merrymaking to distract him, both from his health issues and the stresses of court. Charles’s wife, Isabeau, had arranged a masquerade to celebrate the marriage of one of her ladies-in-waiting. For a laugh, Charles and a group of his mates decided to disguise themselves as ‘wild men of the woods’ and perform a dance routine for the amusement of the guests. This involved highly flammable costumes made of flax, pitch and resin. The men capered around, challenging the guests to guess who was behind the masks.

Then Charles’s brother, the Duke of Orleans, turned up. Late. Sh*tfaced. And holding a lit torch.

There are several versions of what happened next. Some say the Duke of Orleans held up his torch to identify one of the dancers and a spark fell onto the man’s outfit. Another version - which is a contemporary account - says that Orleans threw his torch at the dancer.

Either way, the result was the same. Within seconds, their costumes caught fire and several of the men were engulfed in flames, burning alive in front of the horrified court. Michel Pinton, a chronicler of Charles VI’s reign, didn’t hold back when he wrote “four men were burned alive, their flaming genitals dropping to the floor ... releasing a stream of blood.” The flames jumped from the dancers to the guests, as the fire began to rage out of control. It was sheer luck that the king happened to be off to one side talking to his aunt, who quickly threw her voluminous dress over him to shield him from the flames. Another of the men quickly jumped into a vat of wine. The other dancers died, including the lad who’d come up with the bright idea in the first place, cursing until the bitter end.

This horror story became known as the Bal des Ardents or ‘Ball of the Burning Men’ and it had consequences far beyond the terrifying spectacle which had unfolded in front of the court. When the public found out, they were furious! To them, the ball symbolised everything that was wrong with the aristocracy - decadent, irresponsible, reckless. The Duke of Orleans became the lightning rod for their anger. Some accused him of sorcery, claiming he had tried to murder the king with black magic.

The outcry was so strong that the royal family had to publicly atone for such foolishness. They attended a special religious service of penance and then - in a scene straight from Game of Thrones - had to do a walk of shame through the streets of Paris.

The ‘little queen’ and the broken crown

Unsurprisingly, the Bal des Ardents shattered what little stability Charles had left. His delusions worsened. His relationship with Isabeau disintegrated. At times, he didn’t even recognise her, growing confused and agitated in her presence.

Into this void stepped Odette de Champdivers, a young woman introduced to court through her father’s service in the royal household. She first appears in records around 1405, not as a courtesan or social climber, but as a carefully selected companion. While chroniclers are often vague, later accounts suggest that Odette bore a striking resemblance to a younger Isabeau and this may have played a crucial role in her acceptance by the king.

Odette became a psychological surrogate, allowing the court to maintain a manageable daily routine for the king while avoiding the disruptions caused by Isabeau’s presence. The queen, still very much a political actor, appears to have accepted this arrangement and seemed happy to return to Charles’s side during his lucid moments, as evidenced by her continued pregnancies.

At court, Odette came to be known as ‘the little queen’. The moniker carried layers of irony and recognition. She held no official status and never sought political power, yet she performed many of the queen’s functions in the king’s private life. She oversaw his personal care, soothed him during episodes of confusion, and offered companionship in the long silences of his illness. (Fun fact: she’s the person who introduced playing cards to France as a way of entertaining Charles.) Her presence allowed the king a rare sense of calm in a world that was increasingly hostile, unfamiliar, and fragmented.

But what happens when a monarch is incapable of ruling? If there’s one lesson we can learn from history, it’s that a royal court abhors a vacuum. There was no formal mechanism to declare Charles unfit. No abdication. No legal transfer of power. Instead, the court waited. It adjusted. It lied when necessary. But this fragile dance could not continue for long. Behind the scenes lurked an estranged wife, a “regicidal” younger brother, and members of France’s increasingly divided royal houses - all of whom felt they should rule. Factions emerged. Loyalties shifted. Civil war loomed. And all the while, Charles drifted further into his illness.

Things get even more dramatic in the next part of this tale, which has enough murder and betrayal to put George RR Martin to shame! If you can’t wait to find out what happens next, paid subscribers can get early access to Part 2 - read it here.

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