Franco-Spanish victory Cobelligerent: Charles Rigault de Genouilly François Page Léonard Charner Louis Bonard Carlos Palanca Gutiérrez The Cochinchina campaign[1] was a series of military operations between 1858 and 1862, launched by a joint naval expedition force on behalf of the French Empire and the Kingdom of Spain against the Nguyễn period Vietnamese state.

Gia Long contended that the French government had failed to honor the Treaty of Versailles (1787) and assist him in the civil war since those who had helped him, such as Pierre Pigneau de Behaine, were volunteers and adventurers, not officials.

Advanced fortification methods and technologies had already been adopted and implemented as trained Vietnamese planners had successfully reproduced the elaborate 18th century Vaubanesque citadel of Saigon built by French engineers.

In November 1857, Napoleon III, emphasizing the rationale of Mission Civilisatrice, authorised Admiral Charles Rigault de Genouilly to lead a punitive expedition against Vietnam.

The French and Spanish, who had captured the city in a marine assault found themselves in no position to progress further inland and were pinned down in a long siege by a Vietnamese army under the command of Nguyễn Tri Phương.

[13] Realising that the French garrison at Tourane was not to achieve a strategic success shortly, Charles Rigault de Genouilly pondered options of operations in either Tonkin or Cochinchina in October 1858.

Jauréguiberry's small detachment suffered substantial losses in a surprise attack on a Vietnamese fortification to the west of Saigon on 21 April 1859 and was forced to remain inside its defence perimeter thereafter.

In November 1859, Rigault de Genouilly was replaced by Admiral François Page, who had been instructed to obtain a treaty with focus on the protection of the Catholic faith in Vietnam and not to seek any territorial gains.

[citation needed] The Vietnamese, aware of France's distraction in Italy, refused these moderate terms and spun out the negotiations in the hope that the allies would cut their losses and abandon the campaign altogether.

On 18 November 1859 Page bombarded and captured the Kien Chan forts at Tourane, but this allied tactical victory failed to change the stance of the Vietnamese negotiators.

A naval contingent of 70 ships under Charner (who was now in charge of all land and sea forces) and 3,500 soldiers under the command of General de Vassoigne were transferred from northern China to Saigon.

It included the steam frigates Impératrice Eugénie and Renommée (Charner and Page's respective flagships), the corvettes Primauguet, Laplace and Du Chayla, eleven screw-driven despatch vessels, five first-class gunboats, seventeen transports and a hospital ship.

However, a flotilla of warships under the command of Admiral Page, sent by Charner to approach up the Mekong river to attack Mỹ Tho by sea, appeared off the town on the same day.

A mere fortnight later Bonard mounted a major campaign to overrun Đồng Nai Province in reprisal for the loss of the French lorcha Espérance and all her crew in an ambush.

[27] Admiral Bonard's forces proceeded by capturing Vĩnh Long on 22 March 1862 in a brief punitive operation of Vietnamese guerrilla attacks on French troops around Mỹ Tho.

[29] The loss of Mỹ Tho and Biên Hòa and the fall of Vĩnh Long seriously worsened the strategic situation for the Court at Huế and in April 1862 Tự Đức announced that he wished to make peace.

The sequel was described by Colonel Thomazi, the historian of the French conquest of Indochina: On the third day, an old paddlewheel corvette, the Aigle des Mers, was seen slowly leaving the Tourane River.

[31] The expedition had turned out to be longer and costlier than initially thought and from a position of strength the French intended to fully enforce their conditions of military and colonial dominance.

[32] Tự Đức's minister Phan Thanh Giản signed a treaty with Admiral Bonard and the Spanish representative Colonel Carlos Palanca Gutiérrez on 5 June 1862.

The Treaty of Saigon required Vietnam to legalize the free practise of the Catholic faith within its territory, to cede the provinces of Biên Hòa, Gia Định and Định Tường and the islands of Poulo Condore to France, to allow the French to trade and travel freely along the Mekong River, to open the ports of Tourane, Quảng Yên and Ba Lac (at the mouth of the Red River) to trade and to pay an indemnity of one million dollars to France and Spain over a ten-year period.

In 1867 Admiral Pierre de la Grandière forced the Vietnamese government to cede the provinces of Châu Đốc, Hà Tiên and Vĩnh Long to France.

The Vietnamese emperor Tự Đức initially refused to accept the validity of this cession, but eventually recognized French dominion over the six provinces of Cochinchina in the 1874 Treaty of Saigon, negotiated by Paul-Louis-Félix Philastre after the military intervention of Francis Garnier in Tonkin.

[35] Perhaps the most important factor in Tự Đức's decision to make peace was the threat posed to his authority by a serious uprising in Tonkin led by the Catholic nobleman Le Bao Phung, who claimed descent from the old Lê dynasty.