In his account of battle of Marathon in 490 B.C., the Greek historian Herodotus recorded the story of a man that went inexplicably blind after witnessing the death of one of his comrades. Until recently, this was believed to be earliest-known record of what modern medicine calls post-traumatic stress disorder.

But now, as BBC News reports, a team of researchers says they’ve found references to PTSD-related symptoms in much earlier writings, dating from the Assyrian Dynasty in Mesopotamia, between 1300 B.C. and 609 B.C. They published their findings in the journal Early Science and Medicine with an article poetically titled “Nothing New Under the Sun.”

Soldiers in ancient Assyria (located in present-day Iraq) were tied to a grueling three-year cycle, the BBC notes. They typically spent one year being “toughened up by building roads, bridges and other projects, before spending a year at war and then returning to their families for a year before starting the cycle again.”

By studying translations of known texts, the historians were able to see just how familiar symptoms of PTSD might have been to Assyrian soldiers. Co-author of the study and director of the Anglia Ruskin University’s Veterans and Families Institute, Professor Jamie Hacker Hughs told BBC News:

"The sorts of symptoms after battle were very clearly what we would call now post-traumatic stress symptoms. "They described hearing and seeing ghosts talking to them, who would be the ghosts of people they'd killed in battle - and that's exactly the experience of modern-day soldiers who've been involved in close hand-to-hand combat."

As the study’s abstract states, the researchers also found instances of soldiers reporting “flashbacks, sleep disturbance and low mood."

PTSD wasn’t clinically recognized in the U.S. until 1980, following a surge in classifiable cases from soldiers returning home from the Vietnam War. Before that, terms like “shell shock” were used to describe post-combat psychological struggles, and many soldiers, either because of external pressures or their own feelings of shame, kept quiet about emotional injuries first sustained in war.

This new research helps to demonstrate that, despite only recently receiving wide recognition, the correlation between war and post-traumatic stress is likely as old as human civilization.