In 1392, is established the Joseon dynasty (1392–1897) after a coup d’état that overthrew the Goryeo dynasty in 1388. King Sejong the Great (1418–1450) implemented numerous administrative, social, scientific, and economic reforms, established royal authority in the early years of the dynasty, and personally created Hangul, the Korean alphabet.
After enjoying a period of peace for nearly two centuries, the Joseon dynasty faced foreign invasions and internal factional strife from 1592 to 1637. Most notable of these invasions is the Japanese invasions of Korea, which marked the end of the Joseon dynasty’s early period. The combined force of Ming dynasty of China and the Joseon dynasty repelled these Japanese invasions, but at a cost to the countries. Henceforth, Joseon gradually became more and more isolationist and stagnant. By the mid 19th century, with the country unwilling to modernize, and under encroachment of European powers, Joseon Korea was forced to sign unequal treaties with foreign powers. After the assassination of Empress Myeongseong in 1895, the Donghak Peasant Revolution, and the Gabo Reforms of 1894 to 1896, the Korean Empire (1897–1910) came into existence, heralding a brief but rapid period of social reform and modernization. However, in 1905, the Korean Empire signed a protectorate treaty and in 1910, Japan annexed the Korean Empire. Korea then became a Japanese colony from 1910 to 1945.
In 1866, reacting to greater numbers of Korean converts to Catholicism despite several waves of persecutions, the Joseon court clamped down on them, massacring French Catholic missionaries and Korean converts alike. In response France invaded and occupied portions of Ganghwa Island. The French army occupied Ganghwa Island, an island near Seoul, and tried to advance to Seoul, but failed due to strong resistance from the Korean army, and then withdrew from the island.
The General Sherman, an American-owned armed merchant marine sidewheel schooner, attempted to open Korea to trade in 1866. After an initial miscommunication, the ship sailed upriver and became stranded near Pyongyang. After being ordered to leave by the Korean officials, the American crewmen killed four Korean inhabitants, kidnapped a military officer and engaged in sporadic fighting that continued for four days. After two efforts to destroy the ship failed, she was finally set aflame by Korean fireships laden with explosives.
This incident is celebrated by the DPRK as a precursor to the later USS Pueblo incident. In response, the United States confronted Korea militarily in 1871, killing 243 Koreans in Ganghwa island before withdrawing. This incident is called the Shinmiyangyo in Korea. Five years later, the reclusive Korea signed a trade treaty with Japan, and in 1882 signed a treaty with the United States, ending centuries of isolationism.