The Invisible Wounds of War: From Ancient Battlefields to PTSD

A soldier can come home without a visible wound and still never truly leave the battlefield.

For as long as human beings have made war, those who survived it have carried more than scars, broken bones, and missing limbs. They have carried memories. Nightmares. Fear. Guilt. Anger. Exhaustion. A nervous system that refuses to stand down.

Today, we have a name for one of the most serious forms of this suffering: post-traumatic stress disorder, or PTSD.

But the diagnosis is relatively new. The suffering is not.

The history of war is also, in many ways, a history of humanity struggling to understand what happens to the mind and body after exposure to extreme violence. Across the centuries, the same basic mystery appears again and again: Why does a person who survived the battlefield sometimes continue to fight the battle long after the fighting has stopped?

The vocabulary changed. The explanations changed. The treatments changed.

The wound remained.

The Ancient Battlefield

Some of the earliest written evidence of psychological reactions to warfare comes from the ancient world.

Medical historians have identified descriptions from ancient Mesopotamia, including accounts from the Assyrian period, that appear to describe symptoms we might recognize today as trauma-related: disturbed sleep, intrusive experiences, low mood, and other changes following combat. The ancient explanation, however, was not psychiatric. Such suffering could be understood through a spiritual framework, including the idea that the spirits of people killed in battle might return to trouble the survivor.

Perhaps the most famous ancient example comes from the Greek historian Herodotus.

At the Battle of Marathon in 490 BCE, Herodotus tells the story of an Athenian soldier named Epizelus. Epizelus was fighting in close combat when he suddenly lost his sight, despite having suffered no physical injury to his eyes. He later described seeing a towering warrior who passed him and killed the man fighting beside him.

Epizelus remained blind for the rest of his life.

For more than a century, physicians and historians have returned to this story as a possible early description of psychological trauma manifesting through the body. Some have compared it to what we now call conversion disorder or combat-related trauma. But modern scholarship urges caution: there is no consensus that Epizelus can legitimately be diagnosed with a modern psychiatric disorder. His story existed within the religious and cultural world of ancient Greece, where visions and divine intervention had meanings very different from our own.

That distinction matters.

The point is not that Herodotus somehow anticipated the DSM.

The point is that human beings were noticing the strange aftermath of terror long before they possessed the medical language to explain it.

The Soldier Who Came Home but Did Not Return

For centuries afterward, descriptions of war trauma appear sporadically in literature, medicine, religion, and personal accounts.

The terminology varied enormously.

A soldier might be described as melancholy, nervous, exhausted, hysterical, cowardly, possessed, or simply unable to cope. What we now understand as psychological injury was frequently interpreted as a weakness of character or a physical disorder.

And this division between mind and body would become particularly important in the nineteenth century.

The Industrial Revolution and the rise of modern warfare produced new kinds of trauma. Railway accidents, industrial disasters, artillery, mass armies, and increasingly destructive weapons forced physicians to confront people who appeared physically intact but were profoundly changed.

One of the most important American examples emerged during the Civil War.

The American Civil War and “Soldier's Heart”

The American Civil War produced casualties on a scale that overwhelmed the medical systems of both armies. Doctors encountered injuries they had never seen in such numbers—but they also encountered soldiers whose suffering did not fit neatly into the category of a physical wound.

Among the physicians treating Union soldiers was Jacob Mendes Da Costa, who worked at Satterlee Hospital in Philadelphia.

There, he observed hundreds of soldiers suffering from a puzzling collection of symptoms: rapid heartbeat, palpitations, shortness of breath, sweating, fatigue, dizziness, and weakness. Many had no obvious structural abnormality of the heart.

In 1871, Da Costa described what he called “irritable heart.”

The condition eventually acquired several names, including Da Costa's syndrome, soldier's heart, effort syndrome, and neurocirculatory asthenia.

The name tells us something about nineteenth-century medicine.

Doctors could see that something was wrong.

They could measure the pulse. They could listen to the heart. They could observe breathlessness and exhaustion.

But they did not yet have a satisfactory explanation for how extreme psychological stress could produce such powerful physical effects.

So the wound was often described through the body.

The heart became the battlefield.

Modern research has drawn interesting connections between the physiological stress responses observed in these soldiers and what we now know about the relationship between chronic stress, cardiovascular systems, and PTSD. But it would be an oversimplification to equate every case of Civil War “soldier's heart” with modern PTSD. The syndrome encompassed a broader and medically distinct collection of symptoms.

Still, something important had changed.

Military medicine was beginning to recognize that a soldier could be incapacitated by war without having a bullet in his body.

World War I: When the Battlefield Entered the Nervous System

Then came industrialized warfare.

The First World War transformed the scale and intensity of combat. Soldiers lived for months in trenches while artillery bombardments shook the ground around them. Men witnessed death on an industrial scale. There was little protection from constant noise, fear, exhaustion, and the knowledge that an artillery shell could arrive without warning.

And suddenly, military hospitals were filled with men whose bodies appeared strangely intact.

They trembled.

They could not sleep.

Some could not speak.

Some developed paralysis or blindness without an identifiable physical injury.

Others suffered nightmares, confusion, panic, exhaustion, or overwhelming fear.

The term that came to dominate the early discussion was shell shock.

At first, the explanation seemed straightforward: perhaps the enormous explosions of artillery were physically damaging soldiers' brains. But physicians began noticing that men who had never been close to an exploding shell could develop similar symptoms.

The theory had to change.

Shell shock might not simply be the result of physical concussion.

It might be the consequence of terror itself.

The realization was profoundly uncomfortable.

If psychological trauma could disable a soldier, what did that say about courage? About masculinity? About military discipline?

Some soldiers were treated compassionately. Others were accused of cowardice or weakness. Treatments varied and could include rest, hypnosis, hydrotherapy, electrical treatments, and attempts to restore soldiers' ability to function. In some cases, the objective was not necessarily recovery in the modern sense but getting the soldier back to useful civilian life—or back to the front.

The First World War therefore created one of the great turning points in the history of invisible wounds.

The problem could no longer be ignored.

There were simply too many men suffering.

Between the Wars: The Name Changes, the Problem Doesn't

The story did not end with the Armistice.

Military physicians continued to encounter what were variously called war neuroses, neurasthenia, effort syndrome, neurocirculatory asthenia, and other conditions. Some were understood primarily as physical illnesses; others were considered psychological.

The terminology itself reveals how uncertain medicine remained.

One generation called it soldier's heart.

Another called it shell shock.

Another called it war neurosis.

The same fundamental question persisted:

What happens to a human nervous system when it has been forced to live in mortal danger for too long?

World War II brought the question back on an even larger scale.

World War II and “Battle Fatigue”

By the Second World War, military psychiatry had learned some lessons from 1914–1918.

The term battle fatigue became increasingly common, along with combat exhaustion and combat stress reaction.

Military psychiatrists recognized that otherwise healthy soldiers could break down under prolonged combat conditions. The solution increasingly involved rapid intervention near the battlefield, rest, reassurance, and returning soldiers to functioning as quickly as possible.

There was still an assumption, however, that many combat reactions were temporary.

The expectation was often that a soldier would recover once removed from the immediate danger.

For many, that happened.

For others, the war followed them home.

And that became increasingly difficult to explain.

Korea, Vietnam, and the Long Shadow of War

After World War II and the Korean War, the medical establishment continued to struggle with the long-term consequences of combat.

The problem became impossible to overlook after Vietnam.

American veterans returned to a society deeply divided over the war. Many struggled with nightmares, intrusive memories, avoidance, emotional numbing, anger, hypervigilance, depression, substance use, and difficulties reconnecting with civilian life.

Veterans and researchers increasingly used the term post-Vietnam syndrome.

But something larger was happening at the same time.

Researchers were discovering that similar psychological patterns appeared not only among combat veterans but among survivors of other kinds of overwhelming trauma—including Holocaust survivors and victims of sexual violence and abuse.

The implications were enormous.

Perhaps the problem was not simply “what war does to soldiers.”

Perhaps the underlying phenomenon was what extreme trauma can do to human beings.

Research involving Vietnam veterans became an important part of the eventual recognition of PTSD, alongside advocacy by veterans, Holocaust survivors, feminist movements, and others seeking recognition of the long-term consequences of traumatic experiences.

1980: PTSD Gets a Name

In 1980, the American Psychiatric Association published the third edition of its Diagnostic and Statistical Manual of Mental Disorders.

For the first time, post-traumatic stress disorder—PTSD—was formally recognized as a psychiatric diagnosis.

It was a watershed moment.

For centuries, people had experienced the consequences of catastrophic violence.

Now medicine had a diagnostic framework for understanding them.

One of the most significant conceptual changes was that PTSD located the cause of the disorder outside the individual.

The problem was not necessarily an inherent weakness.

The person had encountered something overwhelming.

The event mattered.

That represented a major departure from older ideas of “traumatic neurosis” and from the tendency to interpret psychological collapse as evidence of defective character.

The diagnosis did not solve everything.

But it gave clinicians and patients something enormously important:

a language.

The Invisible Wound Becomes Visible

The history of PTSD is therefore not simply the story of a diagnosis.

It is the story of a gradual change in how society understands suffering.

Ancient writers described strange physical and psychological reactions to battle but explained them through the beliefs of their time.

Civil War physicians saw exhausted, frightened soldiers whose hearts raced and whose bodies seemed unable to recover.

World War I physicians confronted shell shock.

World War II produced battle fatigue and combat exhaustion.

Vietnam veterans and researchers challenged the idea that these reactions were merely temporary.

And in 1980, PTSD finally entered the official diagnostic vocabulary.

The progression can look deceptively simple:

Ancient trauma → soldier's heart → shell shock → war neurosis → battle fatigue → post-Vietnam syndrome → PTSD.

But history was never that tidy.

These conditions were not simply identical disorders waiting for someone to give them the correct name. Each existed within a particular culture, military system, medical theory, and understanding of human nature.

The names changed because society's understanding changed.

The Battle Doesn't Always End When the Shooting Stops

Perhaps that is the most important lesson in the history of invisible wounds.

For a soldier in ancient Greece, trauma might be understood through gods, spirits, honor, fate, or the battlefield itself.

For a Civil War physician, it might appear as an irritable heart.

For a British soldier in the trenches, it might be shell shock.

For a World War II soldier, battle fatigue.

For a Vietnam veteran, post-Vietnam syndrome.

Today, we may call it PTSD.

But behind all those terms is a profoundly human reality.

The nervous system is designed to protect us from danger. Fear, vigilance, rapid heartbeat, heightened awareness—these are not failures. On a battlefield, they can keep a person alive.

The problem comes when the body and mind cannot recognize that the war is over.

A sound that once meant incoming artillery may become a car backfiring.

A smell may bring back a dead comrade.

A crowded room may feel dangerous.

Sleep may become a place where the battlefield returns.

And memories may arrive without permission.

The soldier has left the war.

The war has not necessarily left the soldier.

From Shame to Recognition

Perhaps the most remarkable part of this history is not the discovery of PTSD itself.

It is the gradual erosion of the belief that psychological suffering is evidence of cowardice.

That idea has haunted soldiers for centuries.

The language changes, but the accusation is familiar: Why can't you just get over it?

History gives us a different answer.

Because the human mind and body can be profoundly altered by extreme experience.

Because survival itself can have a cost.

Because an invisible wound can be every bit as real as a visible one.

And because recognizing that wound is not an act of weakness.

It is an act of understanding.

The history of war is usually written in battles, victories, defeats, maps, weapons, and casualty figures.

But there is another history running underneath it.

It is the history of the people who came home carrying what no surgeon could remove.

For thousands of years, humanity has struggled to name those wounds.

We finally have one of the names.

PTSD.

But the search for understanding began long before the diagnosis—and it is still continuing today.