American intelligence officer Frank Manuel started seeing the symbol near the end of World War II, etched across white walls in the Franconia region of Germany: a straight vertical line intersected by a horizontal line with a hook on the end. “Most members of the Counter Intelligence Corps were of the opinion that it was merely a hastily drawn swastika,” Manuel wrote in a memoir. But Manuel knew otherwise. To him, the mark referred to the Werewolves, German guerrilla fighters prepared “to strike down the isolated soldier in his jeep, the MP on patrol, the fool who goes a-courting after dark, the Yankee braggart who takes a back road.”

In the final months of World War II, as the Allied troops pushed deeper into Nazi Germany and the Soviet Red Army pinned the German military on the Eastern front, Hitler and his most senior officials looked to any last resort to keep their ideology alive. Out of desperation, they turned to the supernatural for inspiration, creating two separate lupine movements: one, an official group of paramilitary soldiers; the other, an ad hoc ensemble of partisan fighters. Though neither achieved any monumental gains, both proved the effectiveness of propaganda in sowing terror and demoralizing occupying soldiers.

From the start of the war, Hitler pulled from Germanic folklore and occult legends to supplement Nazi pageantry. High-level Nazis researched everything from the Holy Grail to witchcraft, as historian Eric Kurlander describes in his book, Hitler’s Monsters: A Supernatural History of the Third Reich. Among those mythological fascinations were werewolves. “According to some 19th and early 20th century German folklorists, werewolves represented flawed, but well-meaning characters who may be bestial but are tied to the woods, the blood, the soil,” Kurlander says. “They represented German strength and purity against interlopers.”

It was an image Hitler harnessed repeatedly, from the name of one of his Eastern front headquarters—the Wolf’s Lair—to the implementation of “Operation Werewolf,” an October 1944 plan for Nazi SS lieutenants Adolf Prützmann and Otto Skorzeny to infiltrate Allied camps and sabotage supply lines with a paramilitary group. Skorzeny had already proved the value of such a specialized strike in 1943, when he successfully led a small group of commandoes to rescue Benito Mussolini from a prison in Italy.

“The original strategy in 1944-5 was not to win the war by guerrilla operations, but merely to stem the tide, delaying the enemy long enough to allow for a political settlement favorable to Germany,” writes historian Perry Biddiscombe in Werwolf! The History of the National Socialist Guerrilla Movement, 1944-46. But that plan failed, in part because of confusion over where the group’s orders came from within the chaotic Nazi bureaucracy, and also because the military’s supplies were dwindling.

The second attempt at recruiting “werewolves” came from Minister of Propaganda Joseph Goebbels—and this time it was more successful. Beginning early in 1945, national radio broadcasts urged German civilians to join the Werewolf movement, fighting the Allies and any German collaborators who welcomed the enemy into their homes. One female broadcaster proclaimed, “I am so savage, I am filled with rage, Lily the Werewolf is my name. I bite, I eat, I am not tame. My werewolf teeth bite the enemy.”

While most German civilians were too exhausted by years of war to bother joining this fanatical crusade, holdouts remained across the country. Snipers occasionally fired on Allied soldiers, assassins killed multiple German mayors working with the Allied occupiers, and citizens kept caches of weapons in forests and near villages. Although General George Patton claimed “this threat of werewolves and murder was bunk,” the American media and the military took the threat of partisan fighters seriously. One U.S. intelligence report from May 1945 asserted, “The Werewolf organization is not a myth.” Some American authorities saw the bands of guerrilla fighters as “one of the greatest threats to security in both the American and Allied Zones of Occupation,” writes historian Stephen Fritz in Endkampf: Soldiers, Civilians, and the Death of the Third Reich.

Newspapers ran headlines like “Fury of Nazi ‘Werewolves’ to Be Unleashed on Invaders” and wrote about the army of civilians who would “frighten away the conquerors of the Third Reich before they have time to taste the sweets of victory.” An orientation film screened for GIs in 1945 warned against fraternizing with enemy civilians, while the printed “Pocket Guide for Germany” emphasized the need for caution when dealing with teenagers. Soldiers on the ground reacted strongly to even a hint of subterfuge: In June 1945 two German teenagers, Heinz Petry and Josef Schroner, were executed by an American firing squad for espionage against the U.S. military.

While the werewolf propaganda achieved Goebbels’ goal of intimidating Allied forces, it did little to help German citizens. “It stoked fears, lied about the situation and lured many to fight for a lost cause,” wrote historian Christina von Hodenberg by email. “The Werewolf campaign endangered those German citizens who welcomed the Western occupiers and were active in the local antifascist groups at the war’s end.”

Local acts of terror continued through 1947 and Biddiscombe estimates that several thousand casualties likely resulted from Werewolf activity, either directly or from reprisal killings. But as Germany slowly returned to stability, fewer and fewer partisan attacks took place. Within a few years, the Nazi werewolves were no more than a strange memory left from the much larger nightmare of the war.

“It’s fascinating to me that even when everything is coming down around them, the Nazis resort to a supernatural, mythological trope in order to define their last-ditch efforts,” says Kurlander. To him, it fits into the larger pattern of Hitler’s obsession with the occult, the hope for impossible weapons and last-minute miracles.

However little effect the werewolves may have had on the German war effort, they never disappeared entirely from the minds of the American media and politicians. According to von Hodenberg, “In American popular culture, the image of the Nazi and the werewolf often merged. This was taken up by the Bush administration during the Iraq War, when Condoleezza Rice, Donald Rumsfeld and President Bush himself repeatedly compared insurgents in Iraq to werewolves, and the occupation of Iraq to the occupation of Germany in 1945.” Even today, analysts have used the Nazi werewolves as a comparison for ISIS fighters.

For Kurlander, the longevity of the Nazi werewolf in the war years belongs to the same longing for myth and magical thinking that Hitler and the Nazis employed. People don’t necessarily want to turn to science and empiricism for answers—they want mysticism to explain problems away. “It’s very seductive to view the world that way.”