Battle of Rufiji Delta The Battle of the Rufiji Delta was fought in German East Africa ( modern Tanzania ) from October 1914 - July 1915 during the First World War , between the German light cruiser , and a powerful group of British warships . The battle was a series of attempts to sink the blockaded German cruiser that eventually resulted in the destruction of " Königsberg " . Background . In 1914 , the most powerful German ship in the Indian Ocean was the light cruiser " Königsberg " . After an engine failure , " Königsberg " — along with her supply ship " Somali " — sought refuge in the delta of the Rufiji River in order to hide while her damaged machinery was transported overland to Dar es Salaam for repair . The British cruiser discovered " Königsberg " in the delta towards the end of October . On 5 November , two additional British cruisers — and — arrived at the scene , and blockaded the German ship in the delta . In early November , " Chatham " opened fire at long range and set fire to " Somali " , but she failed to hit " Königsberg " , which promptly moved further upstream . The British ships were more powerful than " Königsberg " , but were unable to navigate the delta . The crew of " Königsberg " disguised their ship so it looked like the forest around the delta . Blockade . The British made several attempts to sink " Königsberg " including one to slip a shallow - draught torpedo boat ( with escorts ) within range , an operation easily repulsed by the force in the delta . A blockship — the " Newbridge " — was successfully sunk by the British across one of the delta mouths to prevent her escape ; however , it was soon realized that " Königsberg " could still escape through one of the delta ' s other channels . Dummy mines were laid in some of these alternates , but they were considered a doubtful deterrent . A civilian pilot named Cutler was hired to bring his Curtiss seaplane for reconnaissance ; his plane was shot down , although they verified the presence of the elusive cruiser . A pair of Royal Naval Air Service Sopwith seaplanes were brought up with the intention of scouting and even bombing the ship , but they soon fell apart in the tropical conditions . A trio of Short seaplanes fared a little better , managing to take photographs of the ship before they were grounded by the glue - melting tropical heat and German fire . Attempts to use the guns of the old battleship to sink the cruiser were unsuccessful , once again because the shallow waters prevented the battleship getting within range . However , by March 1915 food supplies were low and many of the crew members aboard the died from malaria and other tropical diseases . Generally cut off from the outside world , the morale of the sailors fell . However , the situation was marginally improved with a scheme to resupply the ship and give her a fighting chance to return home . A captured British merchant ship — " Rubens " — was renamed " Kronborg " and given a Danish flag , papers , and a crew of German sailors specially selected for their ability to speak Danish . She was then loaded with coal , field guns , ammunition , fresh water , and supplies . After successfully infiltrating the waters of East Africa , she was intercepted by the alerted , which chased her to Manza Bay . The trapped ship was set on fire by the crew and left . The Germans later salvaged much of her cargo which went on to be used in the land campaign and some transported to the " Königsberg " . Sinking . Two shallow - draught monitor s — and — were towed to the Rufiji from Malta by the Red Sea making it to the delta in June 1915 . With nonessential items removed , added armour bolted on , and covered by a full bombardment from the rest of the fleet , they ran the gauntlet . Aided by a squadron of four land planes — two Caudrons and two Henry Farmans — based at Mafia Island to spot the fall of shells , they engaged in a long - range duel with " Königsberg " , which was assisted by shore - based spotters . Although " Mersey " was hit and the monitors were unable to score on the first day , they returned again on 11 July . Finally , their guns knocked out " Königsberg " s armament and then reduced her to a wreck . At around 14 : 00 , Looff ordered her scuttled with a torpedo . After the battle , the British were unquestionably the strongest naval power in the Indian Ocean . Aftermath . The next day , 33 German dead were buried by the 188 remaining crewmen . A plaque reading " " Beim Untergang S . M . S . Königsberg am 11 . 7 . 15 gefallen . . . " " was placed near the graces , followed by a list of the dead . The Germans recovered " Königsberg " s ten quick - firing guns , mounted them on improvised field carriages , and used them with great success as powerful field guns in their guerrilla campaign against the Allies around East Africa . The guns were used as harbor fortifications in Dar es Salaam , with one being remounted onto the passenger ship " Graf von Götzen " . The last gun was not knocked out until October 1917 . The remaining crew from " Königsberg " went on to serve as ground troops under General Paul von Lettow - Vorbeck . Three of " Königsberg " s 4 . 1 - inch guns survived ; one is on display outside Fort Jesus , Mombasa , Kenya , another outside the Union Building in Pretoria , South Africa and a third at Jinja Barracks in Uganda . There are stories of another in the Congo , but no details have been forthcoming .