Meanwhile, Balhae fell after invasions by the Khitan-led Liao dynasty; fleeing refugees including the last crown prince emigrated to Goryeo, where he was absorbed into the ruling family, thus unifying the two successor states of Goguryeo.
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.
Jeulmun pottery bears basic design and form similarities to that of Mongolia, the Amur and Songhua river basins of Manchuria, the Jōmon culture in Japan, and the Baiyue in Southern China and Southeast Asia.
The founding legend of Gojoseon, which is recorded in the Samguk yusa (1281) and other medieval Korean books,[34] states that the country was established in 2333 BC by Dangun, said to be descended from heaven.
[74] Goguryeo experienced a golden age under Gwanggaeto and Jangsu,[76][77][78][79] who both subdued Baekje and Silla during their times, achieving a brief unification of the Three Kingdoms of Korea and becoming the most dominant power of the Korean peninsula.
At its peak in the 4th century during the reign of King Geunchogo, Baekje absorbed all of the Mahan states and subjugated most of the western Korean peninsula (including the modern provinces of Gyeonggi, Chungcheong, and Jeolla, as well as part of Hwanghae and Gangwon) to a centralized government.
[104][105] Baekje played a fundamental role in transmitting cultural developments, such as Chinese characters, Buddhism, iron-making, advanced pottery, and ceremonial burial to ancient Japan.
The 18th century Joseon dynasty historian Yu Deuk-gong advocated the proper study of Balhae as part of Korean history, and coined the term "North and South States Period" to refer to this era.
Eventually, Kyŏn Hwŏn was ousted by his sons due to a succession dispute and escaped to Goryeo, where he served as a general in the conquest of the kingdom he personally founded.
After defeating the Khitan Empire, Goryeo experienced a golden age that lasted a century, during which the Tripitaka Koreana was completed, and there were great developments in printing and publishing, promoting learning and dispersing knowledge on philosophy, literature, religion, and science; by 1100, there were 12 universities that produced famous scholars and scientists.
[193] Gongmin had various problems that needed to be dealt with, including the removal of pro-Yuan aristocrats and military officials, the question of land holding, and quelling the growing animosity between the Buddhists and Confucian scholars.
[195] In 1392, the general Yi Seong-gye, later known as Taejo, established the Joseon dynasty (1392–1897), named in honor of the ancient kingdom Gojoseon,[12][196][note 3] and founded on idealistic Confucianism-based ideology.
[197] The prevailing philosophy throughout the Joseon dynasty was Neo-Confucianism, which was epitomized by the seonbi class, scholars who passed up positions of wealth and power to lead lives of study and integrity.
His son and grandson, King Taejong and Sejong the Great, implemented numerous administrative, social, and economic reforms and established royal authority in the early years of the dynasty.
Toyotomi Hideyoshi marshalled his forces and tried to invade the Asian continent through Korea, but was eventually repelled by the Korean military, with the assistance of the righteous armies and Chinese Ming dynasty.
The policy had been established primarily for protection against Western imperialism, but soon the Joseon dynasty was forced to open trade, beginning an era leading into Japanese rule.
As a result, the disarray and blatant corruption in the Korean government, particularly in the three main areas of revenues – land tax, military service, and the state granary system – heaped additional hardship on the peasantry.
[209] Animus and persecution by more conservative elements, the Pungyang Jo clan, took the lives of priests and followers, known as the Korean Martyrs, dissuading membership by the upper class.
Arguably of greater influence were the religious teachings of Choe Je-u, (최제우, 崔濟愚, 1824–64) called "Donghak", which literally means Eastern Learning, and the religion became especially popular in rural areas.
Themes of exclusionism (from foreign influences), nationalism, salvation and social consciousness were set to music, allowing illiterate farmers to understand and accept them more readily.
King Gojong's father, Heungseon Daewongun (Yi Ha-ung; 1820–98), ruled as the de facto regent and inaugurated far-ranging reforms to strengthen the central administration.
In addition, Sowon – private academies – which threatened to develop a parallel system to the corrupt government and enjoyed special privileges and large landholdings, were taxed and repressed despite bitter opposition from Confucian scholars.
The king and the royal family were atop the hereditary system, with the next tier being a class of civil or military officials and landowners known as yangban, who worked for the government and lived off the efforts of tenant farmers and slaves.
The Joseon court was aware of the foreign invasions and treaties involving Qing China, as well as the First and Second Opium Wars, and followed a cautious policy of slow exchange with the West.
[220] A rapidly modernizing Meiji Japan successfully challenged China in the First Sino-Japanese War (1894–1895) triggered by the Donghak Peasant Movement, forcing it to abandon its long-standing claims to deference by Korea.
The imperial government aimed to become a strong and independent nation by implementing domestic reforms, strengthening military forces, developing commerce and industry, and surveying land ownership.
[243] This movement was partly inspired by United States President Woodrow Wilson's speech of 1919, declaring support for right of self-determination and an end to colonial rule after World War I.
Koreans in Manchuria formed resistance groups known as Dongnipgun (Liberation Army); they would travel in and out of the Sino-Korean border, fighting guerrilla warfare with Japanese forces.
[258] On June 25, 1950, the Korean War broke out when North Korea breached the 38th parallel line to invade the South, ending any hope of a peaceful reunification for the time being.
After the Soviet Union's dissolution in 1991, the North Korean economy went on a path of steep decline, and it is currently heavily reliant on international food aid and trade with China.