German submarine Deutschland Deutschland was a blockade - breaking German merchant submarine used during World War I . It was developed with private funds and operated by the North German Lloyd Line . She was one of the first of seven U - 151 class U - boats built and one of only two used as unarmed cargo submarines . After making two voyages as an unarmed merchantman , she was taken over by the German Imperial Navy on 19 February 1917 and converted into the " U - 155 " , armed with six torpedo tubes and a deck gun . Construction . " Deutschland " was built together with her sister ship " Bremen " in 1916 by the " Deutsche Ozean - Reederei " , a private shipping company created for the enterprise , a subsidiary company of the North German Lloyd shipping company ( now Hapag - Lloyd ) and the Deutsche Bank . She was constructed without armaments , with a wide beam to provide space for cargo . The cargo capacity was 700 tons ( 230 tons of rubber could be stored in the free - flooding spaces between the inner and outer hulls . ) , relatively small compared to surface ships . " Deutschland " was one of seven submarines designed to carry cargo between the United States and Germany in 1916 , through the naval blockade of the Entente Powers . Mainly enforced by Great Britain ' s Royal Navy , the blockade had led to great difficulties for German companies in acquiring raw materials which could not be found in quantity within the German sphere of influence , and thus substantially hindered the German war effort . Five of the submarine freighters were converted into long - range cruiser U - boats ( U - kreuzers ) equipped with two 150mm deck guns , and only two were completed according to the original design : the " Deutschland " and the " Bremen " , which was lost without a trace on her maiden voyage . Britain and France soon protested against the use of submarines as merchant ships , arguing that they could not be stopped and inspected for munitions in the same manner as other cargo vessels . The US , under diplomatic pressure for supposedly showing favoritism while having declared itself neutral , rejected the argument . Even submarines , as long as they were unarmed , were to be regarded as merchant vessels and accordingly would be permitted to trade . Merchant service . First journey . " Deutschland " departed on her first voyage to the US on 23 June 1916 commanded by Paul König , formerly of the North German Lloyd company . She carried 750 tons of cargo in total , including 125 tons of highly sought - after chemical dye s , mainly Anthraquinone and Alizarine derivatives in highly concentrated form , some of which were worth as much as $ 1 , 254 a pound in 2005 money . She also carried medical drugs , mainly Salvarsan , gemstones , and mail , her cargo being worth $ 1 . 5 million in total . Passing undetected through the English Channel she arrived in Baltimore on 9 July 1916 ( some sources say 7 July ) after just over two weeks at sea . A photograph by Karle Netzer dates the arrival 10 July ( ' erreichte Baltimore Hafen 10 Juli 1916 ' ) . During their stay in the US , the German crewmen were welcomed as celebrities for their astonishing journey and even taken to fancy dinners . American submarine pioneer Simon Lake visited the " Deutschland " while she was in Baltimore , and made an agreement with representatives of the North German Lloyd line to build cargo submarines in the US , a project which never came to fruition . She stayed at Baltimore until 2 August , when she sailed for Bremerhaven , arriving on 24 August with a cargo of 341 tons of nickel , 93 tons of tin , and 348 tons of crude rubber ( 257 tons of which were carried outside the pressure hull ) . Her cargo was valued at $ 17 . 5 million , several times the submarine ' s construction costs . She had traveled , having been submerged for of them . Second journey . The " Deutschland " made another round trip in November 1916 to New London , Connecticut with $ 10 million of cargo including gems , securities , and medicinal products . At the same time the submarine " U - 53 " also crossed the Atlantic to visit Newport , Rhode Island , and sank 5 Allied freighters just outside US territorial limits before returning home . On 16 November as she was trying to put to sea , the " Deutschland " rammed and sank the tugboat " T . A . Scott , Jr . " , with the loss of five men aboard the tug . Her bows were damaged , and she had to return to New London for repairs , which delayed her departure by a week . She finally left New London on 21 November 1916 , with a cargo that included 6 . 5 tons of silver bullion . Following his last voyage , captain Paul König wrote a book ( or possibly had it ghost - written ) about the journeys of the " Deutschland " , entitled " Voyage of the Deutschland , the First Merchant Submarine " ( Verlag Ullstein & Co , Berlin 1916 ) . The book was heavily publicized , as it was intended to sway public opinion in both Germany and the US . War service . A third voyage , planned for January 1917 , was aborted as German - US relations had worsened following the sinking of shipping bound for the United Kingdom , often just outside of US territorial waters . The " Deutschland " was taken over by the German Imperial Navy on 19 February 1917 and converted into the " U - 155 " , part of the U - Kreuzer Flotilla , being fitted with 6 bow torpedo tubes with 18 torpedoes , and two 150mm deck guns taken from the pre - dreadnought battleship SMS " Zähringen " . She made three successful war cruises , sinking 42 ships and damaging one . 1917 . During the summer of 1917 " U - 155 " made a 105 - day cruise , commanded by Karl Meusel , leaving Germany around 24 May and returning on 4 September . During her traverse of the Northern Passage around the northern end of the British Isles and out into the Atlantic Ocean , she was stalked and nearly sunk by U - 19 near Utsira Island , Norway . During her patrol she sank 19 merchant ships , most by either scuttling or gunfire . She attacked 19 Allied armed merchantmen but only succeeded in sinking 9 of them . Upon her return to Germany she had covered a distance of , of which had been travelled submerged , one of the longest voyages made by a U - boat during World War I . 1918 . " U - 155 " sailed from Kiel on 11 August 1918 commanded by Ferdinand Studt . Studt ' s orders directed him to cruise off the US coast in the region of the Nantucket lightship and lay mines off St . John ' s , Newfoundland and Halifax , Nova Scotia . He was also directed to cut telegraph cables off Sable Island , southeast of Nova Scotia . His orders , however , proved problematic , and Studt came to believe that the St . Johns where he was to lay mines was actually Saint John , New Brunswick , in the Bay of Fundy . On " U - 155 " s outbound voyage she had captured and scuttled the Portuguese sailing ship " Gamo " , had attempted an attack on the SS " France " , and destroyed by gunfire the Norwegian " Stortind " . On 7 September " U - 155 " found herself in a long range gun duel with the US steamer " Frank H . Buck " , the steamer later claiming to have sunk " U - 155 " . On 13 September " U - 155 " engaged in another gun fight with the British merchantman " Newby Hall " which managed to damage the submarine , denting her armour and causing serious leaks in her pressure hull which made diving temporarily impossible . On 19 September , Studt tried and failed to locate and cut the telegraph cable near Sable Island , then headed for Nantucket . Fate . " U - 155 " returned to Germany from her final cruise on 12 November 1918 and was surrendered on 24 November 1918 with other submarines as part of the terms of the Armistice . She was taken to Britain and exhibited in London and elsewhere and was eventually sold for scrap in 1921 . On 17 September 1921 she was being broken up at Robert Smith and Sons , Birkenhead , when an explosion ripped the ship apart , killing five apprentices .