Lissin

Unsealed Files · Episode 19 · 5 min · 31 August 2026

Forgotten Infernos: The Halifax Explosion and History’s Hidden Catastrophes

Each week, a buried crime resurfaces—this time, a shipload of explosives turns Halifax into a war zone overnight.

What this episode covers

Step into the shadowy archives of history as we unearth the devastating Halifax Explosion, a catastrophe whose echoes have largely faded from public memory. This episode meticulously reconstructs the events, revealing not just the tragic loss but the profound societal shifts and untold stories that followed. Discover why some historical infernos remain forgotten, and what vital lessons they still hold for us today, presented with the gravitas of a rediscovered, long-lost record.

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Transcript

624 words · the script as narrated

At nine-oh-four and thirty-five seconds in the morning, a ship carrying munitions for the Great War vanished in a flash of white light. Like the corporate violence at Ludlow we examined last week, this was not an act of war, nor an act of God. The file is cold to the touch, filled with nautical charts and telegrams, but the story it tells is one of simple, human error, compounded until it became one of the most violent events in modern history. The story begins with two ships on a collision course in the harbor of Halifax, Nova Scotia, on December sixth, 1917.

The first was the SS Imo, a Norwegian vessel chartered for Belgian relief. It was empty, riding high in the water, and in a hurry. The second was the SS Mont-Blanc, a French cargo ship. It was riding dangerously low. No one in the harbor knew why. No one knew that beneath its decks, the Mont-Blanc was packed with two-thousand three-hundred tons of picric acid, two hundred tons of TNT, ten tons of guncotton, and thirty-five tons of highly flammable benzol stored in barrels on the open deck. It was, for all intents and purposes, a floating bomb, and it was sailing through a busy civilian harbor without a flag to warn of its cargo.

That was the first broken rule. The Narrows, the channel leading out of the harbor, was a place of strict traffic laws. But on that morning, laws were treated as suggestions. The Imo, leaving the harbor, found its path blocked and veered into the wrong lane — the inbound lane. Right into the path of the incoming Mont-Blanc. A series of confused whistle blasts echoed across the water. A last-minute order to reverse engines. But it was too late. The high prow of the Imo crunched into the Mont-Blanc’s forward hold. The impact itself was minor.

But it created sparks. And the sparks found the benzol. Fire erupted instantly across the deck of the Mont-Blanc. The crew, knowing the apocalyptic force sitting beneath their feet, didn't hesitate. They abandoned ship. They rowed for shore, screaming warnings in French to a city that couldn't understand them. For twenty minutes, the burning ghost ship drifted. It became a spectacle. Crowds gathered on the docks. People watched from their office windows. A telegraph operator named Vince Coleman understood the danger. He was about to flee when he remembered a passenger train was due to arrive.

He ran back to his key and tapped out a final message. "Hold up the train. Ammunition ship afire in harbour making for Pier 6 and will explode. Guess this will be my last message. Goodbye." The Mont-Blanc drifted until its hull came to rest against Pier 6. And then, it detonated. The ship, the pier, and the water around it were vaporized by a 2.9-kiloton blast. A pressure wave moved at twice the speed of sound, flattening every structure within a one-mile radius. It created a tsunami that tossed ships onto the shore. It shattered windows fifty miles away.

Two thousand people were killed. Nine thousand were injured, many of them blinded by the flash as they stood watching from their windows. The entire Richmond district of Halifax was simply… gone. As if to add a final, cruel postscript to the tragedy, a blizzard buried the city the next day, dumping over a foot of snow on the thousands who were now homeless, hampering any rescue. The official inquiry found blame everywhere, and nowhere. It was a perfect storm of negligence. The most damning piece of evidence was found later. The half-ton anchor shank of the Mont-Blanc was discovered more than two miles from the harbor, buried in the earth like a tombstone.

About Unsealed Files

Dive into the dusty corners of history where justice was never truly served. Each week, we unearth a forgotten crime, presented as if pulled from an archivist's hidden vault. Discover the untold stories and eerie echoes of the past that demand to be heard again.

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