On July 9, 1916, an unusual vessel suddenly appeared in Baltimore Harbour: a German U-boat, proudly flying the red, white, and black Imperial flag. Yet no warships or gunfire greeted the foreign intruder, for she was on a mission not of war, but of commerce. The 60 metre long, 2,300-ton unarmed vessel, specifically designed to evade British naval blockades, was packed to the gunwales with valuable medicines and dyestuffs, which the Germans hoped to trade with the neutral United States for much-needed raw materials. Her two 1916 voyages remain the only time in history that international trade has been conducted via submarine. This is the unique story of the German U-boat Deutschland.

Within months of the outbreak of the First World War in August 1914, Imperial Germany found herself in a precarious situation, with her ports blockaded by the British Royal Navy and most of her overseas colonies in Africa and the Pacific captured. This to widespread shortages of all sorts of goods – particularly tin, rubber, and other raw materials needed to feed the German war machine. As we’ve covered in our previous video That Time Germany and Britain Conducted a Major Business Deal…in the Middle of WWI, Germany grew so desperate for rubber that in late 1915 they actually brokered a deal to obtain some from their enemy Britain in exchange for high-quality optics like binoculars. But as such agreements could not hope to slake German industry’s insatiable thirst for raw materials, the nation instead looked overseas to the United States – at that time still officially neutral and open to international trade. And while German merchant vessels couldn’t hope to get through the British blockade, perhaps they could go under it.

In early 1916, a private business consortium composed of the North German Lloyd shipping company and the Deutsche Bank formed a subsidiary shipping company known as the Deutsche Ozean-Reederei or DOR, which would conduct commercial trade with the United States via cargo-carrying submarines. To equip DOR’s fleet, the consortium ordered the construction of seven U-151 class submarines, specially designed with an extra-broad, deep hull to maximize cargo capacity. The first two U-151 boats completed, the Deutschland and the Bremen, could carry 700 tons of cargo, including 230 tons of rubber in the free-flooding spaces between her inner and outer hulls. They had a range of 20,000 kilometres, and a top speed of 15 knots surfaced and 7 knots submerged. Befitting their roles as commercial cargo vessels, neither boat carried any offensive or defensive armament.

Deutschland sailed on her maiden voyage on June 23, 1916, commanded by Captain Paul König of the North Lloyd line and with 29 officers and men aboard. Given her limited capacity, her cargo was carefully chosen for maximum trade value, and included 125 tons of synthetic Anthraquinone and Alizarine dyes highly prized by the American textile industry; pharmaceuticals like the anti-syphilis drug Salvarsan; precious gemstones; and mail. In total, her cargo was valued at some $1.5 million USD – nearly $40 million today.

From her home port of Bremerhaven in northern Germany, Deutschland sailed to the island of Heligoland in the North Sea, where she remained for nine days to throw British patrols off her scent. She then sailed for the North Atlantic, taking the northern route over Scotland rather than entering the heavily-patrolled English Channel. In total, Deutschland only travelled 140 kilometres of her 6,100 kilometre journey submerged, sailing the rest of the way on the surface. After a relatively uneventful two-week crossing, at around 1:20 AM on July 9, Deutschland finally arrived off Cape Henry, Virginia, and made contact with the Eastern Forwarding Company tugboat Thomas Timmins, which had been specially modified to tow the submarine into port. At 11:00 PM the two vessels reached Baltimore and Deutschland dropped anchor at the Marley Neck Quarantine Station.

British and French diplomats in the United States were incensed at the Deutschland’s appearance, arguing that since submarines could not be properly stopped and searched for contraband, they should be considered belligerent enemy vessels and they and their crews impounded. The U.S. Government, however, under enormous pressure from Germany to uphold her own neutrality, rebutted that as an unarmed merchant vessel, the Deutschland was free to visit and trade in any neutral port she desired. Indeed, the submarine’s crew were treated like celebrities in Baltimore, being treated to lavish banquets and even an impromptu German Volksfest. During the submarine’s stay, she was visited by American submarine pioneer Simon Lake, who struck an agreement with the North German Lloyd Line to build cargo submarines in the U.S. As we shall see, world events prevented this deal from going through.

Deutschland remained in Baltimore until August 2, when she sailed for Germany loaded with 350 tons of nickel, 100 tons of tin, and 350 tons of crude rubber valued at nearly $18 million dollars – four times what it cost to build her. The boat’s return crossing was once again uneventful, with Deutschland arriving back in Germany on August 25, 1916. While the cargo she returned was minuscule in the grand scheme of German wartime industry, her voyage was a major propaganda coup, demonstrating that the British blockade was not impenetrable. Indeed, to mark the historic voyage, Captain König commissioned German artists Ernst Zehle to design a commemorative medal, which on one side bore a tongue-in-cheek dedication to Lord Robert Cecil, the British diplomat responsible for blockading Germany; and on the other the image of a beaver swimming under a fisherman’s net with the caption “Don’t go over! Go under!”

Shortly after Deutschland’s return, her sister ship Bremen departed Bremerhaven on her maiden voyage, commanded by Imperial Navy Kapitänleutnant Karl Schwarzkopf. Her cargo, bound for Norfolk, Virginia, was much the same as Deutschland’s, though it included financial credits to fund Simon Lake’s cargo submarine scheme. But Bremen never reached her destination, disappearing without a trace. While several theories have been put forward to explain her disappearance, including that she was rammed by a British merchant cruiser, torpedoed by a British submarine, or simply struck a mine, her fate remains a mystery to this day.

In November 1916, Deutschland made a second voyage to the United States, arriving in New London, Connecticut carrying $10 million in gemstones, securities, and pharmaceuticals. On November 17, while traversing Long Island Sound on her return voyage, she accidentally rammed and sank her accompanying tugboat, the T.A. Scott Jr, killing her captain and entire crew. Only captain Hans F. Hinsch of the North German Lloyd liner Neckar, who was supervising the towing operation, survived the sinking. While relatively undamaged, Deutschland returned to New London for minor repairs to her bow before departing again with a cargo that included 6.5 tons of silver bullion. It would prove to be her final commercial venture, for deteriorating relations between Germany and the United States resulted in the cancellation of a planned third voyage. On February 19, 1917, Deutschland was commandeered by the German Imperial Navy and converted into the long-range cruiser submarine or U-Kreuzer U-151. In addition to six torpedo tubes, Deutschland’s uniquely wide hull allowed her to be fitted with more powerful 150mm deck guns, allowing her to pack a punch both surfaced and submerged.

On April 6, 1917, the United States declared war on Germany, officially ending all trade between the two nations. Two months later, U-151 began her naval career. Between June 1917 and November 1918, U-151 made three highly-successful war patrols, sinking 42 ships and damaging three for a total score of 129,000 gross register tons. She returned from her third patrol on November 12, 1918, the day after Germany signed the Armistice with the Entente Powers, and was surrendered to the British at Harwich 12 days later. She was exhibited as a war trophy in London and Liverpool before being sold to a variety of companies, until finally being taken to Birkenhead in late 1921 for scrapping. Yet despite the war having been over for three years, U-151 was not quite finished fighting, for on September 17, 1921 an accidental explosion in her engine room killed five apprentice wreckers.

Born of the peculiar circumstances of the First World War, the two voyages of the Deutschland remain the only occasions in history when open international trade has been conducted by submarine. While Nazi Germany and Imperial Japan did conduct limited trade via submarine during the Second World War, this was more a case of wartime allies exchanging technology and expertise than commercial trade. And while drug cartels have for many years used specialized vessels called narco-submarines to smuggle large quantities of cocaine and other illicit substances, this practice cannot exactly be called “open” – and for more on these often surprisingly sophisticated vessels, please check out our previous video Narco Submarines and the Strange Economics of Cocaine Smuggling.

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