The illnesses of powerful leaders that changed history

Caligula, Caesar and the Czech physician who read history through a neurologist's eyes

When Caligula went from being the great promise of the empire to a bloodthirsty tyrant within months, Roman historians dismissed him with a simple diagnosis: madness. The Czech physician and science writer Iván Lesny was not satisfied with that answer. In his celebrated Report on the Illnesses of the Powerful, published in 1984, he used modern neurology to reinterpret the ailments of great historical figures and the way they shaped their decisions.

Lesny, born in Prague, built a work of popular science that went beyond the medical field. His thesis is provocative: a fever, a fainting spell or an epileptic seizure in a leader can alter the course of a battle or a reign. The book examines Caesar, Caligula and other leaders through the lens of neurology, and became a hit among general readers.

The enigma of Caesar's health

Plutarch and Suetonius left contradictory accounts of Julius Caesar's ailments. Fevers, fainting spells and nightmares are mentioned. Plutarch describes Caesar's flight from Sulla while running a fever, while Suetonius, more prone to gossip, piles up details about his sens life. Some analyses point to epilepsy, but not everything fits: the seizures and nightmares could correspond to narcolepsy or other nervous system disorders. The lack of effective treatments until the 20th century complicates any retrospective diagnosis.

Caligula: madness or organic illness?

Caligula's case is the one that literature and medicine have exploited the most. His change in behavior was attributed to a latent madness that erupted with power, as Albert Camus portrayed in his 1945 drama. Modern studies do not rule out encephalitis or a neurological disorder. The television series I, Claudius, based on Robert Graves, popularized the classic version, but the file remains open.

There is something unsettling in this review: epilepsy, controllable today with phenobarbital since 1912, had no effective treatment until then. Before that, bromide relieved the seizures but sank the mood. The medical history of the powerful shows that the stigma of a poorly understood illness often weighs more than the illness itself.