When Alexander the Great died at the tender age of 32, he had conquered the known world. Many wondered at the time and since what he could have accomplished if he had managed to live longer. A new theory explores the possibility that the young military genius may not have been deceased when he was pronounced dead in June 323 B.C.

Alexander was just 20 years old when he became king of Macedonia following the assassination of his father, Philip II, in 336 B.C. Over the next 12 years, the young monarch set out on a path of conquest, toppling every opposing force that stood in his way.

It was while in Babylon, in the palace of Nebuchadnezzar II, that Alexander fell ill. He had spent a night drinking with the naval officer Nearchus. The next day, he started drinking again with his friend Medius of Larissa. Before long, Alexander felt feverish and began to complain about acute pain in his back as if being stabbed by a spear. The fever worsened and he slowly became unable to move and then unable to speak. When he drank wine, he only became thirstier. The paralysis grew, and eventually, he could not raise his head.

The ancient historian Plutarch wrote Alexander’s biography several hundred years after the king’s death. Drawing on the information available at the time, he noted, “His body, although it lay without special care in places that were moist and stifling, showed no sign of such destructive influence, but remained pure and fresh.” Many at the time took this as evidence of Alexander’s divinity. To modern eyes, this shows signs of something else.

Katherine Hall of the Dunedin School of Medicine at the University of Otago in New Zealand examined the record surrounding Alexander’s death and proposed an interesting — and disturbing — possibility. The brilliant military commander may have been suffering from a neurological disorder called Guillain-Barré Syndrome (GBS), in which the body’s immune system attacks the nerves, leading to eventual paralysis. She suggests Alexander contracted a Campylobacter pylori infection, the “most frequent cause for GBS world-wide,” which set off the autoimmune disorder, a theory she presents in The Ancient History Bulletin.

In a press release, Hall states that most arguments around Alexander’s cause of death focus on his fever and abdominal pain. The description of him remaining of sound mind receives barely any attention. She believes he contracted an acute motor axonal neuropathy variant of GBS which produced paralysis but without confusion or unconsciousness.

Most disturbingly, if Hall’s premise is correct, Alexander the Great probably was still alive when he was entombed, explaining why his body remained fresh for so long. Hall says that once Alexander was paralyzed, his pupils would have been fixed and dilated, and his body may not have been able to regulate his temperature properly, making him cold. Because physicians in the ancient world relied on breath not pulse to determine death, Alexander’s death may have been announced prematurely. “His death may be the most famous case of pseudothanatos, or false diagnosis of death, ever recorded.”

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