SS Mont-Blanc was a cargo steamship that was built in Middlesbrough, England in 1899 for a French shipping company. On Thursday morning, 6 December 1917, she entered Halifax Harbour in Nova Scotia, Canada laden with a full cargo of highly volatile explosives. As she made her way through the Narrows towards Bedford Basin, she was involved in a collision with Imo, a Norwegian ship. A fire aboard the French ship ignited her cargo of wet and dry 2,300 tons of picric acid, 500 tons of TNT, and 10 tons of guncotton. The resultant Halifax Explosion levelled the Richmond District and killed approximately 2,000 people, and the injured may have been about 9,000.