Written by Jesse Beckett and Clare Fitzgerald
Human curiosity has always been drawn to the unexplained, and World War II left behind an extraordinary number of enduring mysteries. Across vast battlefields, secret operations, and rapid wartime technological advances, many people, aircraft, ships, and missions disappeared without clear explanations.
Some of these questions may never be fully solved. Witnesses often took their knowledge to the grave, while the chaos of war destroyed records and evidence that might have provided answers. Still, these gaps continue to capture the attention of historians and enthusiasts, driving ongoing research, debate, and speculation. What follows are some of the most persistent and intriguing unresolved mysteries of the Second World War.
Foo fighters
Strange things in the sky have always captured the human imagination—and World War II pilots had their share of bizarre encounters. Throughout the war, Allied airmen reported unexplained aerial phenomena: glowing orbs, fast-moving lights, and odd shapes that flew alongside their planes. These strange sightings became known as “foo fighters.”
Initially, U.S. military leadership brushed off the reports, attributing them to combat stress, fatigue, or atmospheric anomalies. But the sheer number of similar accounts from experienced pilots couldn’t be ignored for long. Concern grew that these might be advanced Axis technology, though the fact that the objects never attacked made that theory harder to support.
Despite investigations, no definitive explanation ever emerged. Whether it was a natural phenomenon, experimental tech, or something else entirely, the mystery of the foo fighters remains unresolved.
We’re not saying it was aliens… but it definitely wasn’t nothing.
Disappearance of Flight 19
The Bermuda Triangle is often linked to strange events, making it unsurprising that one of the most bizarre mysteries occurred there just months after World War II came to a close. On December 5, 1945, the US Navy sent 14 aviators on a navigational training mission, which took them through the Bermuda Triangle, a notorious stretch of the Atlantic Ocean known for unexplained disappearances and odd occurrences.
Shortly after takeoff, all five General Motors TBM Avengers lost communication with their base. An investigation was launched to determine what happened, and while an initial conclusion was drawn, it was later retracted. To this day, the case remains unsolved, with the disappearance of the airmen still marked as “cause unknown,” as they were never recovered.
Adding to the enigma, the aircraft sent to search for the missing bombers, a Martin PBM Mariner, also disappeared, leaving the fate of its 13 crew members a mystery. Such stories make us reconsider the risks of entering that region.
Columbus Globe for State and Industry Leaders
The Führer’s fascination with imposing, symbolic possessions reached far beyond monumental buildings and advanced weaponry. It also included objects intended to project authority and international influence, such as the Columbus Globe. Manufactured in Berlin during the 1930s for prominent government leaders and industrial executives, the globe combined skilled craftsmanship with the Führer’s ambition for global supremacy.
Following Germany’s surrender, the globe disappeared, and no reliable record has revealed its fate. Although comparable examples from the same era occasionally appear at auction, none have been conclusively linked to the Führer. It may have been destroyed or misplaced during the war’s chaotic closing days, or perhaps removed by a soldier and retained in a private collection, where it could remain out of public view.
Battle of Los Angeles
One of the most unusual incidents of the Second World War was undeniably the so-called Battle of Los Angeles. What makes it so remarkable? Simply put, it never actually took place. At that time, California was consumed by fears of a potential Japanese invasion, further stoked by rumors of their proximity to the US mainland.
The alleged “battle” occurred following the Ellwood bombardment, prompted by a warning from the Office of Naval Intelligence that predicted an imminent attack on California within the next 10 hours.
In the early hours of February 25, 1942, radar systems detected what appeared to be hostile activity 120 miles west of Los Angeles, setting off the air raid sirens. Over the next few hours, the 37th Coastal Artillery Brigade fired 1,400 shells into the sky, while residents reported sightings of Japanese aircraft, paratroopers, and even unidentified flying objects (UFOs).
In the end, the city faced no actual danger, and the US Navy credited the chaos to heightened fears. However, the incident remains wrapped in mystery, with many feeling that no explanation provided so far fully explains the events of that night.
Who turned in Anne Frank and her family?
One of the greatest unsolved questions of World War II is how the German authorities in the Netherlands located the Frank family’s secret hiding place. Their experience became known around the world through the diary of Anne Frank, who was 15 years old when it was written, and the book has since become a standard part of school curricula in many countries.
The Frank family was arrested in 1944, and Otto Frank, Anne’s father, was the only member of the family to survive the war. Almost eight decades later, no definitive answer has emerged as to who informed on them. In 2022, the book The Betrayal of Anne Frank: A Cold Case Investigation claimed to identify the person responsible, but its publisher later withdrew the book after specialists challenged the reliability of its conclusions.
Gold Train
The mysterious Gold Train is one of the most famous unsolved World War II puzzles. While accounts differ, many believe the German Army loaded a train with gold, art, treasure, and other valuable items when they knew they were losing the war. The train was supposedly hidden in a sealed tunnel and has never been discovered. If it’s real, the treasure could be worth millions, not to mention the incredible history behind it.
More from us: 10 Surviving Buildings from Germany’s Era of Power
The story has turned into an urban legend, but that hasn’t stopped people from taking it seriously. After the war, the Polish military searched for the train but found nothing. No proof has been found to show it ever existed. However, a few years ago, two Polish men claimed they had heard a deathbed confession revealing the train’s location.
Once again, no Gold Train was found.