The Merchant Navy in World War II

After the First World War King George V, in recognition of the contribution made to the British war effort by merchant ships, granted the title of ‘Merchant Navy’ to non-military sailors. As the outbreak of World War II edged closer in 1939, the British merchant fleet remained the largest in the world, employing some 200,000 men and women. This number made up around one third of the entire global merchant fleet at the time, with many of the seamen coming from all over the Empire, including India, Hong Kong and West Africa.

After the declaration of war in September 1939, the Ministry of Shipping – then under the control of Lieutenant-Colonel Sir John Gilmour – took control of the merchant fleet. It was the job of the Ministry to decide what cargo the ships would carry and the function they would fulfil in order to best support the war effort, while crewing and provisioning remained under the jurisdiction of the shipping industry. 

Particular emphasis was put on implementing the convoy system, by which warships would customarily escort groups of merchant ships to deter attacks from German U-boats. With all of Britain’s oil arriving by sea, half of her food, and most of her raw materials – more than a million tonnes per week, in total- the smooth functioning of the merchant fleet was integral to the nation’s survival.

The struggle for control over the Atlantic shipping routes, which would eventually become known as the ‘Battle of the Atlantic’, was one of the longest campaigns of WWII. Germany turned submarines, battleships, aircraft and mines on Britain’s supply lines, while British and American shipyards worked tirelessly to replace those ships that were sunk.

Despite sharing the word ‘Navy’ in their titles, the difference between the Royal and Merchant Navies was that sailors in the latter were classed as civilians. After the outbreak of war, Germany declared that every vessel of the British mercantile marine was to be regarded as a warship, meaning that the sailors of the Merchant Navy faced tremendous risks. Tragically, 30,248 merchant seamen lost their lives during World War Two, a death rate proportionally higher than in any of the armed forces.

Main image: Allied convoy crossing the North Atlantic in 1942 during World War 2. (BSLOC_2013_11_114) Everett Collection Mary Evans