King Henry VI began his reign at a young age and inherited both the English and French crowns. During his reign he had periods of debilitating mental instability. Some have even dubbed him Mad Henry. At times, his unpredictable periods of mental illness left him completely unable to speak or move, let alone rule, while the country was deep in a war for the English crown.
Despite the best efforts of those around him, Henry managed to do some unfortunate things during his reign, with some pretty serious consequences (like losing the crown). Henry VI's mental illness was intermittent, but ongoing. Check out this list for everything we know about his undiagnosed illness.
When Henry fell into a completely unresponsive state in 1453, his wife was pregnant with his first son. Normally, this would be a moment of great happiness, especially to a king who desperately needed a male heir. But when his son Edward was born, the king didn't seem to acknowledge him. When his son was shown to him, he glanced at him and then just looked away. When Henry VI came out of his unresponsive state later, he had to be reminded that he had a son.
Henry's illness altered him physically as well as mentally. When affected, he was unable to move his limbs or even hold his own head up, staying in a slouched position when unsupported. He was physically unresponsive to the world around him. A modern diagnosis would likely be catatonic schizophrenia, but at the time, they really had no idea what to make of it.
The reign of Henry VI occurred during a turbulent period in English history. At the time, a massive struggle was taking place between the Houses of York and Lancaster over claims to the English throne in what's referred to as the War of the Roses. Henry VI found himself at the helm of the Lancastrian forces... at least for a little while. His spells made it nearly impossible for him to maintain a tight grasp on his military, and during one of his spells, he was displaced by Richard, the Duke of York as Protector of the Realm. From there, things worsened for the Lancasters, with the lack of leadership creating civil unrest and competing claims for control of the Lancastrian forces.
Naturally, the events that occurred right before Henry VI's breakdown are a good place to turn when searching for clues about what might've led to the monarch's rapid spiral into madness. According to historian David Grummit, one possible catalyst could've been a shocking reversal of military fortunes in the War of the Roses that Henry learned about just a few days before his mental breakdown.
Essentially, Henry's forces, led by the Earl of Shrewsbury, launched a poorly planned assault on French gun emplacements in the town of Castillon, and Shrewsbury was killed in battle. Henry received the news of this unexpected turn of events in early August, returned to his hunting camp at Clarendon and collapsed into his stupor by August 5th. While historians can't be sure if the shock of Shrewsbury's death gave Henry a mental breakdown, they are sure that the two events are closely linked on Henry VI's timeline of mental illness.