The combined military exercise between the U.S. and the Republic of Korea called Ulchi Freedom Guardian ended Sept. 1 after two weeks of strategic and simulated defense operations from a fictional North Korean attack. This annual exercise was named for a famous Korean general from the Goguryeo Kingdom who is symbol of victory against all odds.
From the first century BC to much of the first century, Korea was in the age of "The Three Kingdoms Period." The Three Kingdoms Period consisted of three rival states, "Goguryeo," "Baekje" and "Silla," occupying all of the Korean peninsula and parts of Manchuria (now land belonging to China and Russia). Among the three Kingdoms, Goguryeo had the largest territory, dominating the entire northern part of the peninsula and Manchuria with its powerful military.
Meanwhile, the large territory was a double edged sword for Goguryeo as it had to share its borders with three rival Kingdoms, Silla, Baekje and also the Chinese Sui dynasty. In the early seventh century, the adjacency of different kingdoms resulted in frequent wars all over the cardinal points, bringing constant threats to Goguryeo's stability. The Battle of Salsu River was one of the largest threats Gogureyo had to face and, during this war, General Eulji Mundeok rose to become the hero of Goguryeo.
In the early seventh century, Emperor Yang of the Sui dynasty decided to launch an attack on Goguryeo. He led 1,133,000 troops and more than two million auxiliaries towards Goguryeo, incapacitating Goguryeo's border defenses. In response to Yang's impending threat, Eulji Mundeok was commissioned as the field general by King Yeonyang of Gogureyo, commanding an army of 300,000 to stop Yang's army from further intrusion.
Sui's troops advanced across the Liao River quickly, and then to the city of Yodong. However, they came to a deadlock as Eulji's troop's succeeded in defending Yodong city. To find a way out of the impasse, Sui's troops turned their target to the city of Pyeongyang. For Eulji, Sui's choice was a welcoming decision as Eulji had full knowledge over the geographical features of the route towards Pyeongyang. He had the conviction that he could cut the supply centers of Sui's army and eventually trap them around the river streams. In order to do this, Eulji lured Sui's troops inside the river streams by engaging them in fights at times and places of his choosing. The records say that he went through seven small engagements and attempted seven retrograde operations to bring Sui's troops deeper towards Pyeongyang.
As Eulji succeeded in bringing Sui's army within six miles from Pyeongyang, he mocked the enemy commander in a letter saying that Sui's army had successfully invaded enough Gogureyo territory and that it was best for both Kingdoms to a ceasefire. In light of the fact that Sui's army marched on foot with only few leaders supplied with horses all the way to Pyeongyang, Eulji's offer was very reasonable. On that account, the Sui army retreated back to Sui. Meanwhile, the core strategy of Eulji was focused on Sui's army crossing the river of Salsu while retreating. Eulji waited for one-third of Sui's army to cross the river, the other third crossing the river, and the rest waiting to cross the river. As soon as the condition was set, Eulji called for an attack, and his 300,000 men wiped out Sui's army, leaving only 2,000 men to retreat.
Eulji's advanced strategy brought victory to Goguryeo and emboldened the Korean people. In addition, Eulji's achievement symbolizes the belief that numbers do not determine victory or defeat.

1) Photo of Eulji
General Eulji Mundeok was a legendary military figure who helped to control the Goguyreo era in the first century. This picture is intended to depict what Eulji looked like although there is no historical record of his actual appearance. Moreover, there is no historical record of Eulji Mundeok's life apart from his great victory in the battle of Salsu River.
2) Photo of three kingdoms
This photo is the map of the Three Kingdoms Period consisting of the three rival states, "Goguryeo," "Baekje" and "Silla," occupying all of the Korean peninsula and parts of Manchuria (now land belonging to China and Russia). At the very end of the Three Kingdoms Period, the Silla kingdom claims victory in bringing the three states under one rule as the united, or "Tongil" Silla.

3) Photo of battle of salsu river
This drawing depicts General Eulji Mundeok calling for an attack on Sui's army. As drawn in the photo, Sui's troops are attempting to cross the river of Salsu while Eulji's troops ambush Sui's army. This surprise attack made it possible for Eulji to achieve a victory over Sui's one million troops.