An American ship, the General Sherman, set out for Korea in 1866, sailing from Tientsin for the purpose, it was rumoured, of plundering the royal tombs at Pyeng-yang.  It entered the Tai-tong River, where it was ordered to stop.  A fight opened between it and the Koreans, the latter in their dragon cloud armour, supposed to be impervious to bullets, sending their fire arrows against the invaders.  The captain, not knowing the soundings of the river, ran his ship ashore.  The Koreans sent fire boats drifting down the river towards the American ship.  One of them set the General Sherman in flames.  Those of the crew who were not burned on the spot were soon slaughtered by the triumphant Korean soldiers.  A more disreputable expedition, headed by a German Jew, Ernest Oppert and an American called Jenkins, left Shanghai in the following year, with a strong fighting crew of Chinese and Malays, and with a French missionary priest, M. Feron, as guide.  They landed, and actually succeeded in reaching the royal tombs near the capital.  Their shovels were useless, however, to remove the immense stones over the graves.  A heavy fog enabled them to carry on their work for a time undisturbed.  Soon an angry crowd gathered, and they had to return to their ship, the China.  They were fortunate to escape before the Korean troops came up.  The American consular authorities in Shanghai placed Jenkins on trial, but there was not enough evidence to convict him.

The killing of the crew of the General Sherman brought the American Government into action.  Captain Shufeldt, commander of the Wachusset, was ordered to go to Korea and obtain redress.  He reached the mouth of the Han River, and sent a message to the King, asking an explanation of the matter.  He had to retire, owing to weather conditions, before the reply arrived.  The Korean reply, when eventually delivered, was in effect a plea of justification.  The Americans, however, determined to inflict punishment, and a fleet was sent to destroy the forts on the Han River.

The American ships, the Monacacy and the Palos bombarded the forts.  The Korean brass guns, of one and one-half inch bore, and their thirty pounders, could do nothing against the American howitzers, throwing eight and ten inch shells.  The American Marines and sailors landed, and in capturing a hill fort, had a short, hot hand-to-hand battle with the defenders.  The Koreans fought desperately, picking up handfuls of dust to fling in the eyes of the Americans when they had nothing else to fight with.  Refusing to surrender they were wiped out.  Having destroyed the forts and killed a number of the soldiers, there was nothing for the Americans to do but to retire.  The “gobs” were the first to admit the real courage of the Korean soldiers.