The World War II traitors contributed to years of brutality and violence, which claimed millions of innocent lives, by helping the enemy.
But when the war finally ended, they faced nations that wanted revenge.
What came next was one of the harshest and most brutal paybacks Europe had ever seen.
Long before shooting started in 1939, Europe was already tearing itself apart.
When Adolf Hitler took power in Germany in January 1933, he didn’t just rebuild an army.
He rebuilt a whole mindset of total loyalty to the state.
Anyone outside that loyalty became a target, and anyone willing to serve Germany became useful.
Italy had already gone down the same path.
Benito Mussolini had ruled since 1922, and by the mid-1930s, both countries were feeding off each other’s ambitions.
Germany left the League of Nations in 1933, reintroduced military conscription in 1935, and marched troops into the demilitarized Rhineland in 1936.
Each move made Europe more nervous.
By March 1938, Germany swallowed Austria during the Anschluss.
Later that same year, they seized the Sudetenland from Czechoslovakia after the Munich Agreement.
Both events showed that Europe was heading toward a huge conflict.
No one knew the exact date, but they could feel it.
This tension created the perfect environment for secret deals, hidden loyalties, and early signs of betrayal.
Some people supported their governments and prepared for the worst.
Others saw rising Germany as a chance to gain money, influence, or revenge.
Germany’s Abwehr, led by Admiral Wilhelm Canaris, moved early.
In 1934, they began quietly recruiting foreigners who were angry, desperate, or simply greedy.
By 1936, they had informants spread out across France, Poland, Britain, Czechoslovakia, and the Balkans.
Many were low-level workers, including factory hands, drivers, and port clerks, people who thought passing information was harmless.
It didn’t feel like treason yet, because there was no war.
But the governments they betrayed were preparing.
France expanded its treason laws in 1938 after years of internal political crisis.
Britain introduced the Treachery Act in May 1939, just four months before the shooting began.
Poland added the death penalty for wartime betrayal even earlier, in 1936, anticipating what Germany was planning.
When Germany attacked Poland on September 1, 1939, the world finally shifted from tension to open war.
Britain and France declared war on Germany on September 3, and suddenly, every country understood the danger of insiders secretly working for the enemy.
The first major example came from Poland.
Germany crushed the country in only five weeks, ending in early October.
During that short but brutal period, the chaos created openings for betrayal.
Some civilians guided German soldiers to hiding spots where Polish officers were regrouping.
Others revealed supply routes or pointed out where resistance fighters lived.
These acts didn’t cause immediate punishment because Poland was still fighting, but they were remembered.
After the war, many of these early collaborators were identified by name and held accountable.
In Britain, the war had barely begun when the first traitor surfaced.
George Johnson Armstrong, a British engineer, was caught passing secrets to Germany in October 1939.
His trial took place in 1941, and he became the first British citizen executed under the Treachery Act in July 1941.
France faced a more complicated problem.
By early 1940, German agents were already working inside the country, helping prepare for the invasion that arrived in May 1940.
One early informant, Pierre Fournier, leaked details about weak spots in the French army’s defenses.
Germany used this kind of information in their fast-moving attacks.
When France collapsed in June 1940, thousands of people who had quietly helped the Germans thought the new Vichy government would protect them forever.
They believed they had chosen the “winning” side.
But that false sense of safety didn’t last long.
Because once the war swung the other way, these names would come back up, one by one.
By mid-1940, much of Europe was under German control.
Norway fell in April 1940.
The Netherlands and Belgium collapsed in May.
France was split in June.
Everywhere Germany marched, it offered the same deal: obey or be crushed.
Some people resisted.
Others chose the easier path of collaboration.
In Norway, Vidkun Quisling stepped forward almost immediately.
On 9 April 1940, the same day Germany invaded, he announced his own government.
His party, Nasjonal Samling, supported the occupiers fully.
Quisling’s police helped arrest thousands of Norwegians, including teachers, officers, and resistance members.
Families who resisted found their loved ones taken to camps such as Grini.
By 1945, when Norway was liberated, the country remembered every decision he made.
His own name later became a worldwide nickname for “traitor.
” In the Netherlands, Anton Mussert and his movement, the NSB, aligned themselves with the Nazis.
When the Germans occupied the country, his supporters helped enforce the new rules.
They pointed out Jewish families hiding in basements, reported resistance meetings, and sometimes even patrolled streets with German soldiers.
Whole neighborhoods later remembered exactly who had collaborated and who had stayed loyal.
Belgium faced a similar story.
Léon Degrelle, leader of the Rexist Party, openly supported Hitler.
He recruited Belgians to fight in German units, especially the Waffen-SS.
Young men joined believing they were fighting against communism, but their decision meant leaving their own country behind.
Many were killed on the Eastern Front.
Those who returned in 1945 came back to a Belgium that no longer wanted them.
And then there was France.
After the defeat in June 1940, the country was split into two zones.
The Vichy government, led by Marshal Philippe Pétain, controlled the south.
While some French citizens simply tried to survive, others actively helped the German occupiers.
They enforced orders, handed over political opponents, and even helped round up Jewish families.
These decisions would come under intense scrutiny when France regained control in 1944.
When Germany launched its huge invasion of the Soviet Union on 22 June 1941, it opened a front unlike anything Europe had ever seen.
It stretched from the Baltic Sea all the way to the Black Sea.
Entire cities fell in days.
Millions of soldiers and civilians were trapped between two systems that were both ruthless in their own ways.
In the middle of this disaster, thousands of people faced impossible decisions.
Some Soviet citizens had old resentments that Germany used to its advantage.
In Ukraine, many families still remembered the Holodomor famine that killed millions in the early 1930s.
In Latvia, Lithuania, and Estonia, people remembered how the Soviets had occupied their lands in 1940 and arrested thousands.
In Belarus, entire villages had been crushed by Soviet policies.
Even in parts of Russia, there were people who had lost relatives during Stalin’s purges.
When German soldiers arrived in 1941, some locals saw them as a lesser evil, or at least as a ticket to survival.
German commanders moved fast.
They created local police units called “auxiliary forces.
” By the end of 1941, more than 80,000 locals had joined these groups.
Their job wasn’t frontline fighting.
They patrolled captured towns, guarded supply routes, and carried out arrests.
Some ended up participating in brutal actions against civilians, especially in areas where partisans were active.
Every name on those rosters would later end up on Soviet lists of “traitors to the motherland.
” But not everyone joined willingly.
Some were pressured.
Some were starving.
Some believed Germany would win the war and that siding with the “future winner” would save their families.
But once they signed up, their actions were recorded.
And the Soviet Union never forgot.
The atmosphere inside the Soviet Union became even more unforgiving in 1942.
Stalin issued his fierce Order No.
227 in July, which meant no retreat, no excuses.
Soviet troops were punished harshly for falling back.
Retreating soldiers could face execution.
Even being captured by German forces was considered suspicious.
The NKVD, the Soviet secret police, believed that any soldier who survived German captivity might have helped the enemy.
After the war, hundreds of thousands of freed Soviet prisoners were sent to special camps in places like Kazakhstan and Siberia.
Many were interrogated for months.
Some were sentenced to years of labor simply because they had been captured alive.
By now, spying had become one of the most dangerous jobs in the world.
Every country knew that information could change the direction of battles.
This meant that the punishment for anyone caught helping the enemy grew harsher each month.
In Britain, German intelligence tried repeatedly to land agents by parachute.
Very few succeeded.
Most were captured within hours.
The British security services had cracked many German codes, so they were usually waiting for the spies before they even touched the ground.
Those tried under the Treachery Act faced execution if convicted.
Josef Jakobs, a German agent, was captured in January 1941 and executed in August that same year.
There were no second chances.
Inside France, the situation was even more complex.
As German occupation tightened its grip, the French Resistance grew louder and more active.
By 1942, groups like the Maquis had begun collecting the names of anyone suspected of helping German officers.
Some informants were forced into cooperation after torture by the Gestapo.
Others volunteered for money, ration benefits, or power.
But the Resistance didn’t care why they did it.
Once an informant’s name appeared on their list, the punishment was almost always death.
Many of these executions happened quietly in forests, barns, and abandoned houses.
Trials were fast, sometimes only a few minutes, because every delay risked being discovered by German patrols.
Italy became another battleground for betrayal after 25 July 1943, when Mussolini was removed from power.
The country split in two.
The south joined the Allies.
The north became the German-backed Italian Social Republic.
Families were divided.
Old friends turned into informants.
People exposed neighbors out of fear or anger.
As German forces took control of northern Italy, thousands of Italians gave information to them.
But when Italy was liberated in 1945, the very same informants faced brutal retribution.
Italian partisans arrested hundreds in cities like Milan, Turin, and Genoa.
Many were executed immediately by firing squads.
The moment Allied troops landed in Normandy on 6 June 1944, the countdown for collaborators began.
The Germans were still strong, but their days were numbered.
In France, German-backed groups like the Milice, created in January 1943, had spent over a year hunting resistance fighters.
They had arrested families, interrogated young men, and helped the Germans track down anyone suspected of working against the occupation.
When the Allies pushed inland after D-Day, members of the Milice became top targets.
Many fled toward Germany.
Those who stayed were captured quickly.
By August 1944, Paris rose up.
The streets exploded with fighting.
As the city freed itself, people pointed out collaborators hiding in apartments, basements, and even inside churches.
Courts formed quickly once the government returned.
Between 1944 and 1949, more than 750 collaborators were executed legally in France.
Their files still sit in the French national archives today, showing exactly what each person did.
Belgium went through its own wave of arrests in September 1944 when Allied forces liberated Brussels and Antwerp.
The Rexist movement, which had supported Germany since 1940, collapsed almost overnight.
Members tried explaining their actions as political idealism or youthful mistakes.
But Belgian courts focused on one thing, that they had worked with the enemy while the country suffered.
The Netherlands experienced a different kind of anger.
During the harsh “Hunger Winter” of 1944–1945, Dutch families had survived freezing temperatures, empty shops, and almost no food.
Many blamed collaborators who had helped German authorities seize supplies or arrest resistance members.
After liberation in May 1945, more than 150,000 Dutch citizens were taken into custody for collaboration.
Trials lasted for years.
Several were executed.
But nothing matched what happened in Germany itself.
Germany wasn’t only fighting enemies outside its borders.
By 1944, it was terrified of enemies inside its own walls.
Hitler believed that internal betrayal was far more dangerous than any foreign spy.
And things exploded after the failed assassination attempt on 20 July 1944, when officers like Claus von Stauffenberg tried to kill him with a bomb inside the Wolf’s Lair.
Once the plot collapsed, the reaction was brutal.
Hitler felt humiliated.
He felt surrounded by traitors.
So he ordered a massive crackdown that hit every corner of German society.
More than 7,000 Germans were arrested within weeks.
By early 1945, around 4,900 people had been executed.
Many had nothing in common except, they wanted the war to end.
These weren’t foreign agents.
These were respected Germans.
Army officers like Henning von Tresckow, government workers like Eduard Hamm, judges, professors, priests, and even mid-level clerks.
Anyone linked to the conspiracy was marked for death.
Trials were a joke.
The People’s Court, led by Roland Freisler, didn’t bother with evidence.
Hearings sometimes lasted less than 10 minutes.
Sentences were already written before the accused entered the room.
Most were hanged in Berlin’s Plötzensee Prison.
Others were shot in secret locations.
Captured officers were often executed immediately after short military hearings.
Families suffered too.
Under Sippenhaft, entire families could be punished for one person’s “betrayal.
” Some lost their homes.
Others were arrested.
Children were taken away and placed in special state homes.
No one was safe.
By early 1945, Germany was collapsing, and paranoia got worse.
As Allied troops pushed into German territories, the regime doubled down.
Soldiers caught leaving their posts were executed on the roadside by flying courts-martial.
These were small teams that drove around the front lines, handing out death sentences within minutes.
Civilians suffered as well.
Anyone caught helping Allied soldiers risked being shot on the spot.
Local Nazi officials acted on fear, not law.
Some ordered executions without approval.
Hitler Youth boys as young as 15 were used to patrol towns, and some were involved in carrying out executions of so-called “traitors.
” Germany was no longer fighting just the Allies.
It was fighting itself.
Every week, more Germans died at the hands of their own government.
The country was eating itself alive.
When Germany surrendered on 8 May 1945, the world felt a brief moment of relief.
But the relief was mixed with years of anger.
Across Europe, people wanted justice.
And they turned quickly to the collaborators who had helped the Nazis.
France moved fast.
The country had lived under occupation for four long years, and many felt betrayed by those who worked with the German forces.
One of the most famous cases was Pierre Laval, executed on 15 October 1945.
He had helped run the Vichy government and supported German demands.
His trial was quick, and his execution showed how deeply France wanted to close that painful chapter.
In Norway, Vidkun Quisling became the symbol of betrayal.
He was executed on 24 October 1945.
Norwegians saw his execution as a final act of taking their country back.
The Netherlands also acted with determination.
Anton Mussert was executed on 7 May 1946, almost exactly a year after the country was freed.
Belgium took a similar route.
Members of the Rexist Party were executed through 1946.
Poland’s situation was even more intense.
Having suffered some of the worst brutality under German rule, anger ran deep.
By 1946, dozens of collaborators were executed, especially those who had helped the Germans during mass arrests in 1939 and 1940.
Eastern Europe went through some of the harshest reactions.
With Soviet-backed governments taking power, thousands were accused of aiding the Germans.
In Czechoslovakia, public anger was strong, especially after the terror that followed the assassination of Reinhard Heydrich in 1942.
Collaborators faced firing squads, long trials, and sometimes violent mobs before authorities could even intervene.
During this chaos, many collaborators ran.
They knew what was coming.
Some fled to Spain, which was under Francisco Franco and wasn’t eager to hand people over.
Others crossed oceans and hid in South America, with Argentina becoming one of the main safe havens.
The hunt didn’t stop.
France continued searching for missing collaborators throughout the late 1940s.
Some were captured in 1947 and 1948, often living under false names.
Trials continued long after the main wave of justice had passed.
In the Netherlands, smaller trials went on until 1950.
Executions became rare, but the country still wanted answers from those who had vanished during the occupation.
Norway and Denmark finished their last executions in 1948, but they continued arresting suspects who had escaped justice.
Some had been hiding in forests, remote villages, or even across borders.
Poland’s new communist government carried out trials into the early 1950s, especially against people who had worked with German police forces during the darkest years of the war.
The Soviet Union went even further.
Anyone accused of helping the Germans could be sent to labor camps in Siberia.
Many disappeared entirely.
Families often didn’t know if their relatives were alive or dead.
Some cases weren’t closed until decades later, long after the Cold War had begun.
Germany also had its own unfinished business.
After the war, West Germany reviewed the cases of people linked to the 20 July 1944 plot.
For years, families fought to clear their names and remove the label of “traitor.
” Some officers were officially honored only in the late 1950s, showing how long these wounds lasted.
When we look back at all the trials, the firing squads, the rushed decisions, and the long prison sentences, something becomes clear.
The world had just survived the most brutal war in history.
More than 70 million people had died.
In a moment like that, betrayal felt like a knife in the back.
Countries didn’t see traitors as simple criminals.
They saw them as people who helped the enemy destroy their homes.
For many, it felt worse than being attacked by the enemy themselves.
Governments justified executions by saying they needed to restore order.
Courts said they needed to rebuild trust.
Countries believed they needed harsh punishment to move forward.
Communities wanted to show that loyalty mattered.
Families who had lost loved ones demanded justice.
And in a world still shaking from the war’s impact, executing traitors felt like the only way to close the chapter.
