The Korean Expedition (1871), also called the U.S. expedition to Korea, was the first major military action between the United States and Korea’s Joseon Dynasty. The conflict began during a U.S. mission to open trade and establish diplomatic relations.

American diplomats and naval forces traveled to Korea to negotiate a treaty and investigate the earlier destruction of the U.S. ship General Sherman. Korean coastal forts fired on U.S. ships near Ganghwa Island, which triggered a military response.

U.S. sailors and Marines launched assaults on several Korean forts along the Han River. American forces captured the positions after intense fighting and seized weapons and battle flags.

The expedition failed to secure a treaty or open Korea to trade. However, the conflict marked the first direct U.S. military engagement in Korea and influenced future diplomatic relations in East Asia.