940 years ago, troops and people of Dai Viet defeated 300,000 troops of Song Dynasty. That victory leaves us with valuable lessons about military arts. Notably, the art of organizing and using forces in that battle should be studied and applied into wars to defend the Homeland.

A temple of Ly Thuong Kiet at My An commune, Luc Ngan district, Bac Giang province (photo: baobacgiang.com.vn)

In the beginning years of the 1070s, to realize their plot of conquering Dai Viet, the Song Dynasty once again launched an invasion of our country. They mobilized about 300,000 troops (100,000 infantry, 200,000 logistic and naval troops) to invade our country.

Implementing the plan, on December 11th 1077, Song troops were divided into two arms entering our country on ground and water routes. On land, the enemy quickly crossed the border in Lang Son to penetrate further into our territory; however, until January 18th 1077, Song troops reached the north bank of Cau River. They herein divided their troops into two wings: the right wing led by Zhao Xie camped in Nhu Nguyet landing, and the left one led by Guo Kui camped in Thi Cau. Waiting in vain for naval troops to come, Song troops built boats and rafts to cross the river and attack Thang Long, but all the attacks were intercepted by our troops. In addition, Ly Thuong Kiet carried out small-scale battles sporadically attacking Song troop camps to undermine and destroy the enemy strength. When the opportunity came, he mounted a strategic counter-attack to end the war. After nearly 2 months bravely fighting against the enemy, we annihilated above 190,000 enemy fighters and logistic troops and nearly 6,000 their horses, forcing Song troops to retreat back to their country and acknowledge the independence of Dai Viet. That victory results from various elements, but the most far-reaching and important one is the art of organizing and using forces to fight the enemy.

1. Organizing force appropriately to promote strong points of each part, fighting the enemy extensively, from afar to near. With the guideline “to pit the few against the many”, Ly Thuong Kiet deployed forces all over localities to fight the enemy. The force fighting the enemy from afar included militia and ethnic troops of localities, particularly border ones. Those constant battles, on the one hand, created favourable conditions for the regular forces to strengthen a solid and interconnected defensive posture, on the other hand, alleviated the pressure of enemy attacks on Nhu Nguyet river defensive line. Moreover, operations destroying food transport line made the enemy quickly fall when they had to fight for long time. Ly Thuong Kiet also organized a strong naval force (including 20,000 men and 400 ships) deployed in Luc Dau river to assist the force fighting the enemy in the North Bank of Nhu Nguyet river, prevent and break down the enemy raids. Therefore, naval troops of the enemy led by Yang Songxian were defeated by our naval troops led by Ly Ke Nguyen, which left infantry troops of Zhao Jie and Guo Kui isolated.

In Nhu Nguyet river defensive line, Ly Thuong Kiet organized an assembled  force of about 60,000 troops. This is a seasoned force directly led by him to prevent and break down all the enemy attacks, protect the defensive line and keep them away from Thang Long. The force was divided into three parts and garrisoned in three positions, namely Nhu Nguyet, Thi Cau and Phan Dong. In each position, a part from infantry force, Ly Thuong Kiet also organized a naval force divided into small teams and equipped with light warships for patrolling, destroying the enemy reconnaissance units and preventing the enemy from crossing the river. Besides, Ly Thuong Kiet organized mobile forces being ready to assist and work with the on-spot forces to fight the enemy. That method of focused force organization both brought into play strong points of each force and created an intertwining posture to fight the enemy in the front, the rear and on the two flanks, which destroyed the enemy strength, foiled “speedy fight,   rapid victory” plan of the enemy, and then completely defeated their invasion.

2. Using forces flexibly, creating superior strength to defeat the enemy. Ly Thuong Kiet used militia and ethnic troops to ambush the enemy in important areas and positions. These  forces often ambushed the enemy on their two flanks, in their back of marching formation, even when they camped for break and carried the food, which put them into great need for food and medication and undermined their morale. Typical example for using these  forces was when Ly Dynasty mobilized an elite naval force commanded by Princes Hoang Chan and Chieu Van, collaborating with ground forces to ambush Song naval troops, forcing them to retreat back to Dong Kenh river gate. Thus, the plan of the Song Army for rendezvous in Nhu Nguyet river completely failed.

The feature in the art of using force  was also demonstrated when Ly Dynasty carried out strategic counter-attack. Ly Thuong Kiet created diversions by using a part of force to directly attack strong but vulnerable positions in the main direction of the enemy. In this regard, Ly Thuong Kiet used the whole force in the minor direction, including infantry and naval troops to attack the main force of the enemy to annihilate part of the enemy strength, attract and pin the enemy down there, creating favourable conditions for our troops in the main direction to surprisingly attack and destroy the enemy’s minor force. Since the battle would decide the victory of the strategic counter-attack, Ly Thuong Kiet not only used the whole force in the main direction but also mobilized a mobile force in the back directly commanded by him. It could be understood that we did not use the main force to fight against that of the enemy. Instead, we used our superior strength to attack the enemy’s minor force, driving the enemy’s main force to exhaustion and desperation.

Facing our enormous strength, more than half of the enemy troops was killed. In that moment, we could mobilize our forces to annihilate the rest of the enemy troops and end the war; however, with the tradition of friendliness, Ly Thuong Kiet proactively sent negotiators for a reconciliation with Song troops. That was a flexible way to end the war  in order not to sacrifice any more lives of troops.

The victory in Nhu Nguyet river is down to the past but still gives us valuable lessons on military arts. The lesson on organizing and using force  remains valid and should be studied and applied to the cause of Homeland protection today, particularly to defensive operations at levels to firmly safeguard the Homeland.

Senior Colonel, Assoc Prof. Duong Hong Anh, PhD

Vietnam Military History Institute