World War II: The SS Arandora Star is sunk by U-47 in the North Atlantic with the loss of over 800 lives, mostly civilians.

World War II or the Second World War was a global conflict between two coalitions: the Allies and the Axis powers. Nearly all of the world's countries participated, with many nations mobilising all resources in pursuit of total war. Tanks and aircraft played major roles, enabling the strategic bombing of cities and delivery of the first and only nuclear weapons ever used in war. World War II is the deadliest conflict in history, causing the death of 70 to 85 million people, more than half of whom were civilians. Millions died in genocides, including the Holocaust, and by massacres, starvation, and disease. After the Allied victory, Germany, Austria, Japan, and Korea were occupied, and German and Japanese leaders were tried for war crimes.

SS Arandora Star, originally SS Arandora, was a British passenger ship of the Blue Star Line. She was built in 1927 as an ocean liner and refrigerated cargo ship, converted in 1929 into a cruise ship and requisitioned as a troopship in the Second World War. At the end of June 1940 she was assigned the task of deporting interned Anglo-Italian and Anglo-German civilians as well as a small number of legitimate prisoners of war to Canada. On 2 July 1940 she was sunk by a German U-boat off the coast of Ireland with a large loss of life, 805 people.

German submarine U-47 was a Type VIIB U-boat of Nazi Germany's Kriegsmarine during World War II. She was laid down on 25 February 1937 at Friedrich Krupp Germaniawerft in Kiel as yard number 582 and went into service on 17 December 1938 under the command of Günther Prien.

The Atlantic Ocean is the second largest of the world's five oceanic divisions, with an area of about 85,133,000 km² (32,870,000 sq mi). It covers approximately 17% of Earth's surface and about 24% of its water surface area. During the Age of Discovery, it was known for separating the New World of the Americas from the Old World of Afro-Eurasia.