General Steam Nav. Company

General Steam Nav. Company

General Steam Navigation Company and the Manual of the Laws of Naval War

The General Steam Navigation Company, affectionately known as the Navvies, would become a household name after its incorporation on the 11th June 1824; from its headquarters in Trinity Square overlooking the Tower of London, the Company controlled a larger percentage of the Capital’s European trade than any other shipping operation; indeed, many said that it was partially responsible for London’s maritime prosperity. The Company’s war service began at 18.59 on the 31st July 1914: with the outbreak of war just days away, the Admiralty sent the Company a telegram requesting information about the current positions and expected movements of their entire fleet, which they requisitioned for War duties, including mine-laying, mine-sweeping, flotilla and squadron supply, Fleet messengers and troop transports, as well as the carriage of thousands of tons of goods by sea for stores and ammunition for the troops and parcels sent from home[1].

By the time when Germany was preparing to mobilize in the high summer of 1914, the concept of total war had already been planned by the British Government, in the form of a blockade that was intended to starve Germany of food and materials for the war effort. In modern history, blockades had become commonplace: Napoleon had imposed a blockade of British ports in what he called the Continental System, which was designed to weaken Britain by closing all European ports to British merchant vessels. When the UK responded in 1805 with a blockade of all French ports, they were much more effective. When the Royal Navy intercepted any merchant vessels bound for France, giving the Masters the choice of taking their cargoes to British ports for discharge and sale, or having their ships and cargoes seized under prize laws. More recently, in the American Civil War, the North maintained a tight blockade against Southern ports to achieve the same end, namely to bring the People to their knees. In 1914, with the overwhelming might of the Royal Navy, unrivalled since Nelson’s victory at Trafalgar, there was surely no doubt that a naval blockade of Germany would weaken its ability to prosecute a long war, and the UK drew up plans which could be put into effect immediately upon the outbreak of war[2]. The Government issued a comprehensive list of banned cargoes, as contraband of war, which all but prohibited neutral States trading with the Central Powers and, in November 1914, declared the North Sea to be a War Zone, with any ships entering the North Sea doing so at their own risk. The Northern Patrol and Dover Patrol closed off access to the North Sea and the English Channel respectively; henceforth, the Royal Navy would stop and search merchant ships to ensure that the blockade was observed. 

The Germans lost no time in retaliating with submarine attacks on merchant ships but, at least in 1914, complied with international rules in naval warfare, which meant that they surfaced before attacking a merchant ship and allowed the crew and passengers to evacuate before its seizure. She could then be sunk or, more profitably, taken to a friendly port by a prize crew where she could be made be the subject of a claim as an action in rem in which the Court determined the status of the condemned property and the manner in which she was to be disposed of, and how the proceeds would be distributed.

The laws of procedure were documented in the Manual of the Laws of Naval War published in 1913[3] which strictly forbade pre-emptive destruction of merchant ships and consequent loss of life on board. Under Article 32, any merchant ship may be summoned to stop, when the belligerent vessel would send a boarding party to conduct a search for illegal cargoes of war.

The Laws of Naval War required that, after the belligerent had fired a warning shot, the merchant ship should then respond by signalling and then stop at once. The Manual does not give advice on what the warship should do if she did not respond, but Article 17 forbade killing or wounding an enemy who had no means of defence; subsection 2 forbade a belligerent from sinking a ship which had surrendered, before having taken off the crew –but was silent on what to do if she did not surrender. Article 18 emphasized that it is forbidden to destroy enemy property, except in the cases where such destruction is imperatively required by the necessities of war or authorized by provisions of the present regulations.

The only exception would be for armed merchant cruisers, which were merchant ships requisitioned by the State, when they would be equipped with guns and given token armoured protection, to serve protecting convoys of merchant ships.  An armed merchant cruiser would have fallen under Article 3 of the Laws of Naval War, as she would have been a private vessel converted into a warship as defined, and commanded by an officer in the state’s Navy List of officers of the fighting fleet. As such, she would have been a warship within the meaning of Section II and subject to the appropriate laws for naval warfare – and her ship’s company were to be treated as prisoners of war under the Hague Convention with Respect to the Laws and Customs of War on Land had been signed by the UK and Germany and came into force in 1900. Chapter II specifically addressed the fair treatment of prisoners of war. Article 4 stated that prisoners of war were in the power of the hostile government and, that, 'They must be humanely treated.'[4]

Merchant seafarers, otherwise, would have to be treated as non-belligerents and interned as civilians; killing in cold blood would be murder and, in the course of hostilities, would evolve under international law as a war crime. This was, indeed, the foundation for the prosecution of offenders at the Leipzig Trials in 1921.

Written by MAT volunteer Dr Simon Daniels.

[1] Cope Cornford, L, 1924, A Century of Sea Trading, A & C Black Ltd, London
[2] Memorandum to War Cabinet on trade blockade. See
[3] Manual of the Laws of Naval War, Oxford, Adopted by the International Institute of International Law, August 9, 1913; see
[4] Annex: Section I Chapter I


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