<P> After enjoying a period of peace for nearly two centuries, the Joseon dynasty faced foreign invasions and internal fractional strifes, beginning in 1592 until 1637 . Henceforth, Joseon gradually became more and more isolationist and stagnant . By the mid 19th century, with the country unwilling to modernize, and encroachment of European powers, Joseon Korea was forced to sign unequal treaties with foreign powers . After the assassination of Empress Myeongseong in 1895, Donghak Rebellions of 1894 - 1895, and Gabo Reforms of 1894 to 1896, the Korean Empire (1897--1910) came into existence and a brief but rapid period of social reform and modernization occurred . However, in 1905, the Korean Empire signed a protectorate treaty and in 1910 Japan annexed the Korean Empire . </P> <P> Korean resistance was manifested in the widespread nonviolent March 1st Movement of 1919 . Thereafter the resistance movements, coordinated by the Provisional Government of the Republic of Korea in exile, were largely active in neighboring Manchuria, China, and Siberia . Figures from these exile organizations would become important in post-WWII Korea . </P> <P> After the end of WWII in 1945, the Allies divided the country into a northern area, protected by the Soviets, and a southern area protected primarily by the United States . In 1948, when the powers failed to agree on the formation of a single government, this partition became the modern states of North and South Korea . The peninsula was divided at the 38th Parallel: the "Republic of Korea" was created in the south, with the backing of the US and Western Europe, and the "Democratic People's Republic of Korea" in the north, with the backing of the Soviets and the communist People's Republic of China . The new premier of North Korea, Kim il - Sung launched the Korean War in 1950 in an attempt to reunify the country under Communist rule . After immense material and human destruction, the conflict ended with a cease - fire in 1953 . The two nations officially remain at war because a peace treaty was never signed . Both states were accepted into the United Nations in 1991 . </P> <P> While both countries were essentially under military rule after the war, South Korea eventually liberalized . Since 1987 it has had a competitive electoral system . The South Korean economy has prospered, and the country is now considered to be fully developed, with a similar capital economic standing to Western Europe, Japan, and the United States . </P>

When was the last time korea was united