General Sherman incident The " General Sherman " incident was the destruction of an armed merchant marine side - wheel steamer that visited Korea in 1866 . It was an important catalyst to the end of Korean isolationism in the 19th century . After passing the Keupsa Gate without permission from the Koreans , the United States merchant ship was attacked and fought for several days before finally being destroyed . Background . In the mid - 19th century , the Great Powers were eager to open up new trade in Asia and began consolidating trade in China and southeast Asia . Japan was also opened up to trade after Commodore Matthew Perry sailed into Uraga Harbor near Edo ( modern Tokyo ) on July 8 , 1853 , and under the threat of force Japan signed the Convention of Kanagawa in 1854 . As early as 1832 discussions of opening up Korea to trade were made by the captain of the , Edmund Roberts , yet in 1844 a draft by the United States Congress was shelved due to lack of interest . The first contact between the US and Korea was not in any way hostile , and in 1853 the , a US gunboat , visited Busan for 10 days while en route to Japan ; her officers dined with local officials . Several Americans who were shipwrecked in Korea in 1855 , 1865 and 1866 were treated well and sent to China for repatriation . However , the Joseon Dynasty court which ruled Korea was well aware of the colonization of China as a result of the First and the Second Opium War and maintained a strict policy of isolationism to avoid a similar fate . Incident . Determined to open Korea to trade , the British trading firm Meadows and Co . , based in Tientsin ( present day Tianjin ) , China , sent the " General Sherman " ( named for William Tecumseh Sherman ) into Korean waters in an attempt to meet with Korean officials and begin negotiations for a trade treaty . The 187 - ton side - wheel steamer reportedly carried a cargo of cotton , tin , and glass , and was heavily armed . The crew consisted of Captain Page , Chief Mate Wilson , 13 Chinese and three Malay sailors . Also on board was the ship ' s owner , W . B . Preston , an American trader , and Robert Jermain Thomas , a Protestant missionary acting as an interpreter . They departed Chefoo ( present day Yantai ) , China on August 9 and arrived on the coast of Korea on August 16 , 1866 . The General Sherman , assisted by Chinese junk boats , entered the Taedong River on Korea ' s west coast sailing towards Pyongyang and stopped at the Keupsa Gate , on the border between Pyongan and Hwanghae provinces . Yu Wautai , captain of one of the Chinese junks , had accompanied Rev . Thomas on his previous trip to Korea ' s Hwanghae province . According to Thomas , Yu had 20 years experience trading with Koreans . Local officials met Captain Page and communicated well enough to learn the ship was interested in trade . The Koreans refused all trade offers but agreed to provide the crew with food and provisions . Page was told to wait while higher level government officials were consulted . However , the General Sherman went further up river and anchored west - side of Pyongyang . Due to the previous month ' s rains and the tides , the depth of the Taedong River was raised unusual high and let the steamer into Pyongyang . Park Gyu - su ( the governor of Pyongyang ) sent his Adjutant - General , Yi Hyon - Ik , to provide the crew with food , but he told captain he should have stayed at the Keupsa Gate . He was again ordered to wait while the Korean ruler was consulted . At the time Korea was ruled by a Regent , the Heungseon Daewongun , in the name of his minor son King Gojong . The Daewongun sent orders that the ship must leave immediately or all aboard would be killed . There is dispute over what happened next . Apparently , the ship ' s crew seized Adjutant - General Yi and his two deputies , who were attempting to pursue a small boat launched from the " General Sherman " with six men attempting to reach shore . According to Governor Park ' s report , another government official , Shin Tae - jung , tried to persuade the crew to release Yi Hyon - ik and his men but failed . Instead , the " General Sherman " moved upstream , firing cannons and eventually anchored at Hwang - gang - jung ( House of Yellow River ) . Governor Park later reported that the ship had fired her guns into the crowd , killing seven and wounding five . Then , five men launched a boat and navigating north of Pyongyang to determine the river ' s depth . The citizens of Pyongyang gathered on the riverbank , shouting for the release of Yi Hyon - ik . A man in the boat ( probably Robert J . Thomas , the only one who spoke Korean ) replied they would give the answer if they were allowed inside Pyongyang city . The crowd started throwing stones at the small boat . Korean soldiers shot arrows and guns at the launch , which retreated back to the ship . The Koreans sent a rescue party and managed to free Yi , but his deputies ( Yoo Soon - won and Park Chi - young ) were killed . The ship eventually turned back and sailed down until she ran aground into Yang - Gak island , an island across from Pyongyang . Fighting continued for the four days , after which the Koreans resorted to fire boats , filled with wood , sulphur and saltpeter . The first two failed to inflict any damage , but the third set the " General Sherman " afire . Unable to stem the flames , the crew jumped into the water , where they drowned or were clubbed to death . According to the Korean Official historical record , " Kojong - silrok " ( Vol . 3 ) , there were two survivors from the initial attack , Robert Thomas and Cho Neung - bong . However , they too were beaten to death . The incident was one reason why the U . S . Navy conducted the 1871 Korea Campaign , which resulted in the death of about 300 Koreans . Five years later Korea was forced to sign a trade treaty with Japan , and in 1882 also signed a treaty with the United States , ending several centuries of isolationism . Disputed account . Koreans claimed that the real purpose of General Sherman was to seek treasures buried in the royal tombs near Pyongyang . The only supporting factor of this claim is that Robert Jermain Thomas , the ship ' s interpreter , asked a Korean undercover officer about whereabouts of white pagoda , which is usually associated with worships . However , in China , it was believed that the royal coffins in the tombs of Pyongyang , where more than one dynasty of Korea lay buried , were of solid gold ; and after the departure of General Sherman to Korea , it was rumored among Westerners in China that General Sherman ' s expedition had something to do with these treasures . The Koreans believed the use of an armed metal - hull gunboat was suspicious in a mission simply for trade . The only ironclad Korean ships were military , and the " General Sherman " was taken to be a warship . Still , two months prior to the " General Sherman " Incident , an armed vessel captained by Ernst Oppert , a German , had visited Korea and made the same demand for trade . Trade had been refused , but Oppert and his crewmen had been well treated and returned to China safely . Oppert returned to Korea in the " Emperor " , which steamed up the Han River near Seoul on the same day that the " General Sherman " left Chefoo . Oppert ' s request for trade was denied and he returned to China without incident . The " Surprise " , an American ship , had been shipwrecked in Chulsan , in Pyong - an Province , on June 24 , 1866 . The crew was not harmed and was sent to China by Governor Park Gyu - su , the same official in charge during the " General Sherman " incident . Beginning in the late 1960s , North Korea ' s government historians began to claim the attack on the " General Sherman " was planned and led by a direct ancestor of North Korean dictator Kim Il - sung . The claim , which had no confirmation in historical records , was part of a campaign to promote the special role allegedly played by Kim Il - sung ' s family in Korean history , and facilitate the transfer of dictatorial power to Kim Jong - il , Kim Il - sung ' s eldest son . The claims are still repeated in North Korean publications , including textbooks . In 2006 , North Korea issued a postage stamp commemorating the sinking of the merchant vessel . The , a U . S . Navy intelligence ship captured by North Korea in 1968 and the only U . S . warship still being held in captivity , is currently moored at what is believed to be the spot where the incident took place .