The Beginning: The Successor to Buyeo
According to information found in the Samguk Sagi, Samguk Yusa, and on the Stele of Gwanggaeto the Great, Goguryeo was founded in 37 BC by a Buyeo prince named Jumong ( 추몽 ), who would later come to be known as King Dongmyeong (Dongmyeongseongwang, or 동명성왕 ). It should be noted however, that a precursor to the eventual Goguryeo state began as early as the 4th century BC.
Jumong was supposedly the son of Yuhwa ( 유화 ), who was the daughter of Habaek ( 하백 ), the god of the Yulu river. Yuhwa was condemned to a mortal life after she disgraced her father and eventually married Geumwa (Geumwawang or 검와왕 - the "wang" title means king), who was king of Dongbuyeo (동부여, which means East Buyeo). Yuhwa was impregnated by sunlight and gave birth to an egg, out of which Jumong was born. Geumwa tried to destroy the egg by feeding it to animals, but the animals instead protected the egg and Geumwa later returned it to Yuhwa. Geumwa's sons were jealous of Jumong and eventually forced him to leave Dongbuyeo. According to the myth, he fled on horseback and when he approached a river, various animals in the water rose up and formed a bridge for him to cross. He eventually established Goguryeo in the land to the south of Buyeo and united all of the tribes in that area.
Goguryeo's close proximity to China, combined with a lack of resources, meant that Goguryeo was destined to become a militaristic society. Warriors in Goguryeo completely dedicated themselves to training for combat, even in times of peace. These highly trained warriors would prove to be very useful once Goguryeo began expansion during the beginning of the first century AD. Goguryeo desired to expand its borders in all directions, which of course led to conflict with China. There were numerous clashes with China during Goguryeo's early years, and these eventually culminated in a war with the Wei Dynasty in 244 AD. Goguryeo also enjoyed frequently raiding the lands of neighboring states, which again was due to the lack of resources within Goguryeo's borders. The states of Okjeo and Dongye came under Goguryeo's control during the reign of King Taejo ( 태조왕, or Taejowang ), who ruled from 53 to 146 AD (although the length of his reign is disputed, this 93 year reign is supposedly the second longest reign in world history).
Goguryeo and the Wei Dynasty were allies following the fall of the Han Dynasty in China. However, in an apparent attempt to expand the borders of Goguryeo, King Dongcheon ( 동천왕 ) attacked one of Wei's outlying districts in 242. This led to two campaigns by the Chinese in 244 and 245. During the invasion in 244, the two armies met at the junction of two rivers in a place called Liangkou. Chinese sources and Korean sources differ on the events that transpired, but both agree that King Dongcheon's army was defeated and that he was forced to return to his capitol city of Hwando ( 환도 ). The Wei army then marched on to Hwando and easily took the city, which again forced King Dongcheon to flee. The Wei army returned to China after destroying the city, but then attacked in 245 after hearing that King Dongcheon had returned to the capitol. King Dongcheon fled again and this time the Wei army proceeded to chase him around various areas of Okjeo. The Wei army eventually lost sight of their intended target and once again returned to China. King Dongcheon was finally able to go back to Hwando, but the city had been reduced to ruins and he decided to move the capitol to Pyeongyangseong ( 평양성 ) in 247. Although Goguryeo was severely damaged by the war with Wei, the state would return to power in about 70 years and become one of the most powerful states in all of Asia.
Gathering Strength: Transformation from a War-torn Country to an Asian Kingdom
Aftermath of War
Wei had an extremely successful campaign against Goguryeo. The once waning influence of the Chinese commanderies was returned to prominence following the Goguryeo-Wei wars. Wei also successfully separated Okjeo and Dongye from Goguryeo control, which severely limited Goguryeo's access to natural resources. So what's a king to do when his once thriving country is reduced to ruins? Well, King Dongcheon decided to move the capitol, restructure the economy and expand to new lands. There were of course some hiccups along the way and Goguryeo had to be continually on the lookout for Chinese invaders, but the country was able to undergo steady growth during the second half of the third century until it really began to gain momentum around the beginning of the fourth century. King Micheon ( 미천왕 ), who ruled from 300 to 331, was finally able to conquer the Chinese commanderies in 313 and as a result rid the peninsula of the Chinese presence.
The Chinese continued to be a nuisance and the state of Former Yan successfully entered the capitol in 342, forcing King Gogukwon ( 고국원왕 ) to flee. The king later returned to the capitol and Goguryeo was now forced to focus on military issues within the Korean peninsula. In 371, the southern Korean kingdom of Baekje attacked Goguryeo. The attack was very successful and Baekje was able to take control of Pyongyang and also kill King Gogukwon.
Back on Track
King Sosurim ( 소수림왕 ), son of King Gogukwon, took control after his father's death and brought about some radical changes that would prove very useful in propelling Goguryeo to its future status as an East Asian power. The king established Confucian academies and also developed a code of laws based upon Confucian principles. In addition, Goguryeo became the first Korean Buddhist state when King Sosurim adopted the religion in 372. The Confucian principles in the code of laws were essential for the successful creation of a centralized state and the adoption of Buddhism provided a sense of national unity. King Sosurim's brother, King Gogugyang ( 고국양왕 ), took power from 384 to 391 and continued to foster the development of Buddhism and Confucianism.
The Apex: The Height of Korean Expansion
Gwanggaeto the Great ( 광개토대왕, the last two symbols are "daewang" and mean "the greatest of all kings" ) took power in 391 and ruled for 22 years. In those 22 years he was able to conquer 64 domains and 1,400 villages. He expanded in virtually all directions and regained some of the territory lost to Baekje, conquered Liao-tung, which was a focal point of conflict between Goguryeo and China, and also took control of parts of Manchuria. Gwanggaeto even defeated Japanese forces when Silla asked for Goguryeo's help in defending themselves from an invasion by Japan. He is a deeply revered figure in Korean history and is one of only two Korean kings (King Sejong the Great of the Joseon Dynasty is the other) to be honored with the title "Great".
King Jangsu ( 장수왕 ) was the son of Gwanggaeto the Great and ruled for 79 years after the death of his father. Jangsu began his rule with the purpose of stabilizing the kingdom after the tremendous expansion that had taken place over the previous 20 years. He also moved the capitol from Gungnae Fortress to Pyongyang. This change indicates the desire for a new metropolitan capitol with economic, political, and social influence. Once Jangsu had stabilized the country he began to change his focus to military conquest. He began by expanding into Chinese territory to the northwest. Moving the capitol to Pyongyang also proved to be a strategic move in that it helped to position Goguryeo for an attack on Baekje, which occured in 475 and resulted in Goguryeo seizing the Baekje capitol of Hansong and beheading King Gaero. These conquests resulted in the height of Goguryeo's power in 476. King Jangsu ruled over a kingdom that extended from parts of China in the west, a good portion of Manchura in the north, and the northern half of the Korean peninsula. King Jangsu finally died in 491 at the age of 97.
Trouble on the horizon
The next two kings continued to rule over the vast domain that had been acquired over the previous 100 years. However, trouble was starting manifest itself as King Munja ( 문자왕 ) began paying tribute to various Chinese kingdoms in order to focus on the escalating tensions with Silla and Baekje. His son, King Anjang ( 안장왕 ), continued to maintain stability, but his assassination in 531 led to an internal power struggle that would eventually doom Goguryeo.
The Decline: Internal Strife and External Pressure
King Anwon ( 안원왕 ), King Anjang's younger brother, took power after the death of Anjang. He ruled over a relatively peaceful period, but a power struggle developed at the end of his reign to decide who would succeed him to the throne. The aristocracy was split in their support and this spelled doom for royal authority in Goguryeo. King Anwon's eldest son, King Yangwon ( 양원왕 ), eventually won the struggle, but his reign was marred by a continual weakening of Goguryeo's power. Silla and Baekje took control of Goguryeo's southern territories and nomadic tribes from Manchura invaded from the north.
Sui launched attacks on Goguryeo in 598, 612, 613, and 614. Despite Sui's persistence, none of these attacks ended well for the Chinese dynasty and their failure ultimately led to the downfall of the Sui Dynasty in 618. It is estimated that the attack in 598 resulted in the deaths of 90% of the Sui troops. The second campaign was even worse. The battle of Salsu River saw 305,000 Sui troops enter battle and only 2,700 live to talk about it. The campaigns in 613 and 614 were both very short-lived and no major battles were fought during these years. Although Goguryeo was able to fend off the Sui invaders, the war with Sui didn't end well for either side and actually contributed to the downfall of both Goguryeo and Sui.
More Problems With China
The fall of the Sui Dynasty was a welcome occurrence for Goguryeo, but unfortunately the dynasty was succeeded by the Tang Dynasty, who also attacked Goguryeo. Tang's first invasion occured in 645 and multiple attempts were made following that year, but none were successful. Goguryeo's ability to fend off the Chinese invaders is arguably one of the most important events in Korean history. The fall of Goguryeo to Chinese forces would have more than likely led to the fall of both Baekje and Silla as well, which would have resulted in a Chinese presence throughout the entire Korean peninsula.
The End: The Beginning of a New Chapter in Korean History
More Internal Conflict
Although not actually crowned as king, Yeon Gaesomun ( 연개소문 ) had controlled the kingdom for over 20 years before his death in 665. King Bojang ( 보장왕 ), the last king of Goguryeo, lived on after Yeon Gaesomun's death, but a power struggle ensued between Yeon Gaesomun's sons for control of kingdom. The official end would not come for three more years, but this conflict all but assured the eventual downfall of Goguryeo.
After conquering Baekje in 660, the alliance of Silla and Tang forces turned their attention to Goguryeo. Goguryeo was at first able to repel the attacks, but was gradually becoming weaker. An attack launched by Silla and Tang in 667 was the straw that finally broke the camel's back and resulted in Goguryeo's surrender in 668. The era of Unified Silla had officially begun.
The Goguryeo kingdom existed for over 700 years and was the largest of the three kingdoms. Following its downfall there were many attempts made to revive the Goguryeo state, but the kingdom was eventually split into two parts, with the northern areas coming under the control of Balhae and the southern areas being controlled by Silla. As mentioned previously, Goguryeo holds a special place in Korean history because of its ability to rid the peninsula of Chinese presence and its ability to withstand the numerous attempted invasions by the Chinese. The modern English name of "Korea" is actually derived from the Goryeo Dynasty, which in turn took its name from Goguryeo.