In 1857, the Vietnamese emperor Tự Đức executed two Spanish Catholic missionaries. This happened because of the prohibition of Catholicism in Vietnam at that time, the Nguyen kings considered Catholicism to be an evil religion. If the execution had happened at a different time, rather than after the tense relationship between Vietnam and France, after two bombardments in Da Nang (1847 and 1856), the French would not have used that as an excuse for the invasion of Vietnam, yet it changed Vietnam forever.
In November 1857, the French emperor Napoleon III authorized Admiral Charles Rigault de Genouilly to launch a punitive invasion to teach the Vietnamese a long-overdue lesson. In the following September, a joint French and Spanish fleet landed at Da Nang, whose fine, sheltered harbor would make it a perfect base for an operation against Dai Nam (Vietnam’s title at that time).
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| Admiral Charles Rigault de Genouilly |
On the afternoon of August 31, the coalition gathered at the coast of Son Tra peninsula (Da Nang), facing Dai Nam's fortresses on the mainland. On the morning of September 1, Admiral Genouilly sent an ultimatum to Dai Nam's army, asking to surrender within 2 hours. After receiving no response within the time limit, the Franco-Spanish coalition opened fire.
In terms of combat forces, the Western coalition has 1 50-gun frigate, 2 12-gun corvettes, 5 transport ships, and one corvette. The landing force consisted of 1000 French soldiers, 550 Spaniards, and 450 Filipino mercenaries. The French hoped that with this large and powerful force, they would be able to attack the capital, Hue, and force the Dai Nam army to surrender quickly.
On the Vietnamese side, they defended in strong fortresses, which Westerners on the scene described as "like what we saw in China", the number of soldiers ranged from 7,000 to 10,000 men, and an unspecified number of cannons and muskets. All were led by General Le Dinh Ly. In addition to the main army of the court, there were also local militiamen.
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| Franco-Spanish warships bombarding the coast |
The western coalition heavily shelled the fortress at Son Tra, opening the battle. After only half an hour, most of the coastal defenses had fallen. Genouilly gave the order to land. Colonel Reynaud, chief of staff in the expeditionary command, was ordered to lead the landing companies of the Némésis, Phlégeton, Primauguet ships, and a detachment of combat engineers ashore. Leaving the boats, the French landed on the right bank, aligned themselves in battle formations, and approached the targets, chanting the slogan "Long live the emperor" (Vive l'Empereur!). Thanks to the effective cannon support of the ships Mitraille, Alarme, and El Cano, the targets were quickly eliminated, although the resistance of the Vietnamese troops was not too bad. An Hai citadel and fortresses of Phong Hai, Tran Duong, and Forts: First, Second, Third, and Fourth were all in the hands of the French. In other words, within the afternoon of September 1, the French army had mastered the entire Tien Sa region.
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| Vietnamese artilleries at Dien Hai citadel |
On the morning of September 2, 1858, the enemy continued to bombard Dien Hai citadel and poured troops to occupy the western area. A line was set up on the Hoa Vang side to stop the enemy. The progress of the battle showed that the enemy could not promote the power of technical weapons to attack massively, but was immediately blocked at Da Nang estuary. This was the result of the fierce resistance of the garrison force under the command of a court that was still full of vitality, with high determination and the support of the people.
After Governor-General Le Dinh Ly was seriously wounded and died by bullets, King Tu Duc appointed Marshal Chu Phuc Minh to be the military governor in place of Le Dinh Ly. On the other hand, Tu Duc sent Nguyen Tri Phuong, the top martial general of the court at that time, who was serving as the chief strategist of Cochinchina to command the Da Nang front instead of Chu Phuc Minh.
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| General Nguyen Tri Phuong |
As a talented martial artist, from the very beginning, Nguyen Tri Phuong correctly assessed the situation, proposed a dynamic and appropriate method of defense and fighting against the enemy. He did not advocate attacking the enemy directly to avoid the enemy's firepower, but encircling and blocking the enemy in coastal areas, intensifying ambushes to fight the enemy, preventing the enemy from contacting their people, evacuated houses, abandoned gardens, isolating and destroying the enemy’s supply lines from providing food in their place.
Also in September 1858, Tran Nhat Hien, captain of the Ky Vu camp, a low-ranking martial officer of the Hue court, offered a secret plan to fight the French. The court approved and allowed it to be implemented: making iron chains to block rivers and Thuan An and Tu Hien estuaries, using small boats to ambush key places.
At the same time, the army and people of Quang Nam province used bamboo crates, wooden crates containing soil, and stones to fill the Vinh Dien river to block the advance of the French invaders. The river was filled, the water would flow to Dai Chiem estuary, so the downstream would dry up, enemy boats cannot enter, Dai Nam’s army and people only have to focus on defending the land front.
In November 1858, French warships attacked the Han River and Nai Hien River (Quang Nam) and were ambushed by the Dai Nam army and people under the command of Dao Tri and Nguyen Duy. A few days later, the French invaders again brought eight warships into the Nai Hien River and were also defeated by troops led by Nguyen Tri Phuong and were forced to flee.
Until the end of 1858, the French army could not expand the area of occupation, breakthrough our defense position, to implement the strategy of fighting and winning quickly.
Regression was not possible. Admiral Genouilly decided to change direction to attack Gia Dinh. At the beginning of February 1859, the French left only a small occupation force in Da Nang and a few battleships commanded by Captain Toyon. The ratio of forces in Da Nang at this time has changed, creating an advantage for Dai Nam. Western reinforcements were then worn down by infectious diseases and the sweltering climate, plus nervous tension. Hundreds of people are estimated to have died from cholera.
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| Burial site of dead Franco-Spanish coalition troops |
In the end, after 18 months of the war in Da Nang (from September 1, 1858, to March 23, 1860), Page - Major General in command of the French-Spanish coalition was ordered by the French Government to withdraw all troops from Da Nang.
This was a glorious victory for the Dai Nam army and people, but it was the only victory in the 26-year war with the French empire. In 1859, the French army attacked Gia Dinh citadel and it fell. Dai Nam's army suffered from failure to failure, until 1884, when the French attacked the capital Hue, the Nguyen government surrendered and the colonial period had started, it lasted 61 years until 1945.