7. The outbreak of World War One
In August, 1914, World War I began in Europe, and the British Navy prepared to make war with its German enemy. The naval war was quickly complicated by the German use of the submarine to attack British shipping. The first submarine to sink a British merchant ship was U-17, which followed the cruiser rules by surfacing, allowing the crew of the merchantman to abandon ship, and then sinking the ship. More British ships followed quickly, and the rate of loss was soon felt in Great Britain. The Admiralty responded with a variety of ways, one of which was arming merchantmen – the Q Ship.
The British decision to arm merchant ships with concealed weapons, and then fire at a submarine which rose to the surface to issue a warning rendered the cruiser rules invalid, at least in the German estimation. It was simply too hazardous for the submarine to surface, not knowing if the ship was an unarmed merchantman or an armed Q Ship. The Germans soon had their own version of the Q Ship, but their existence did little to protect its submarines. The Germans declared the waters around Great Britain to be a war zone, and ships within it were liable to unrestricted submarine attack.