Siege of Saigon

The Siege of Saigon, a two-year siege of the city by the Vietnamese after its capture on 17 February 1859 by a Franco-Spanish flotilla under the command of the French admiral Charles Rigault de Genouilly, was one of the major events of the Conquest of Cochinchina (1858–62). Saigon was of great strategic importance, both as the key food-producing area of Vietnam and as the gateway to Cochinchina.

In 1858, Admiral Charles Rigault de Genouilly attacked Vietnam under the orders of Napoleon III following the failed mission of diplomat Charles de Montigny. His stated mission was to stop the persecution of Catholic missionaries in the country and assure the unimpeded propagation of the faith. For his descent on Vietnam, Rigault de Genouilly had a force of 14 warships, 1,000 French marine infantry, and 1,000 troops from the Spanish garrisons of the Philippines (550 Spanish infantry and 450 Filipino light infantry). The allied force landed at the port of Tourane in September 1858 and occupied the city after a brief bombardment. However, the allies were soon placed under siege by the Vietnamese and, unable to advance inland beyond the protection of the squadron's guns, were effectively immobilised at Tourane.

Realising that the French garrison at Tourane could achieve nothing useful, Rigault de Genouilly decided to strike elsewhere against the Vietnamese. He considered and rejected the possibility of an expedition to Tonkin, and in January 1859 proposed to the navy ministry an expedition against Saigon in Cochinchina, a city of considerable strategic significance as a source of food for the Vietnamese army. The expedition was approved, and on 2 February, leaving capitaine de vaisseau Thoyon at Tourane with a small French garrison and two gunboats, Rigault de Genouilly sailed south for Saigon. His naval force consisted of the corvettes Phlégéton and Primauguet, the gunboats Alarme, Avalanche and Dragonne, the Spanish despatch vessel El Cano and the transports Saône, Durance and Meurthe.

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