SS Mont-Blanc Explosion – 1917

As World War I raged all sorts of unglamorous participants played a part in sustaining global conflict. One such was an unremarkable French tramp steamer, the SS Mont-Blanc. In November 1917 she had collected a cargo of ammunition from New York before sailing to Halifax in Nova Scotia to join a convoy bound for Europe. But as Mont-Blanc entered Halifax Harbor, a relatively minor collision took place with the outbound Norwegian ship SS Imo in the infamous Narrows. It was the sort of maritime accident that happened not infrequently without serious consequences, but this time the result was truly awesome.

Sparks flew as the two ships collided head-on and fire broke out on Mont-Blanc. Unable to reach firefighting equipment, her crew abandoned ship. Some 20 minutes later, just after 09:00, Mont-Blanc’s munitions cargo exploded in a massive fireball, obliterating the ship and sending a vast mushroom cloud high into the sky.

A tsunami swept through the harbor and a pressure wave flattened buildings and felled trees as though they were matchsticks. Burning debris rained in all directions and the other offender, Imo, was cast on shore. The force of the explosion may be judged by the fact that a gun barrel from Mont-Blanc was later found 5.5 km (3.4 mi) away.

Large areas of Halifax and neighboring Dartmouth were completely flattened by the blast, killing countless spectators who had been watching the blazing ship. Many more died in the tsunami and fires that subsequently broke out all over town, trapping and killing hundreds of people. Next day, adding to the misery, a blizzard precipitated a deep layer of snow on the devastated communities, hampering rescue efforts and adding to the huge death toll caused by history’s largest accidental man-made explosion.

When was the SS Mont-Blanc Explosion: December 6 1917

Where was the SS Mont-Blanc Explosion: Halifax, Nova Scotia, Canada

What SS Mont-Blanc Explosion death toll: 2,000 dead and 9,000 injured (estimated).

You should know: Ironically, the crew of the offending Mont-Blanc escaped largely unhurt from the carnage caused by their exploding ship – the only casualty being one seaman killed by falling debris. The French crew were unable to make the clear and present danger apparent to the English-speaking locals, but prudently retreated to a safe distance themselves.