The Halifax Explosion occurred on December 6, 1917, in the harbor of Halifax, Nova Scotia. It was caused by the collision of the French cargo ship SS Mont-Blanc, carrying explosives, with the Norwegian vessel SS Imo. The resulting explosion was one of the largest man-made blasts prior to the atomic bomb, devastating the surrounding area and killing approximately 2,000 people. The explosion destroyed much of the city, leaving around 25,000 people homeless. In the aftermath, relief efforts were organized, including assistance from the Red Cross and neighboring communities. The event highlighted the need for improved safety regulations regarding the transport of hazardous materials.