Region of mainland Southeast Asia. The term, now largely superseded by the name Southeast Asia, was used mainly by Westerners to describe the intermingling of Indian and Chinese cultural influences in the region. Indochinese Peninsula typically referred to Cambodia, Laos, and Vietnam (see French Indochina), though it was sometimes expanded to include Myanmar (Burma), Thailand, and the mainland portion of Malaysia.
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French Indochina (French: Indochine française; Vietnamese: Đông Dương thuộc Pháp, /ɗoŋ jɯəŋ tʰʊək˨ fap˦˥/) was the part of the French colonial empire in Indochina in southeast Asia, consisting of a federation of four protectorates (Tonkin, Annam, Cambodia and Laos) and one directly-ruled colony (Cochinchina). The capital of French Indochina was Hanoi.
In 1858, 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. Rigault de Genouilly, with 14 French gunships, 3,000 men and 300 Filipino troops provided by the Spanish, attacked the port of Danang in 1858, causing significant damages, and occupying the city. After a few months, Rigault had to leave the city due to supply issues and illnesses.
Sailing south, De Genouilly then captured the poorly defended city of Saigon on 18 February 1859. On 13 April 1862, the Vietnamese government was forced to cede the territories of Biên Hòa, Gia Định and Dinh Tuong to France. De Genouilly was criticized for his actions and was replaced by Admiral Page in November 1859, with instructions to obtain a treaty protecting the Catholic faith in Vietnam, but not to try to obtain territorial gains. In 1864 all the French territories in southern Vietnam were declared to be the new French colony of Cochinchina. In 1867 the provinces of Châu Đốc, Ha Tien and Vĩnh Long were added to French controlled territory.
In 1863, the Cambodian king Norodom had requested the establishment of a French protectorate over his country. In 1867, Siam (modern Thailand) renounced suzerainty over Cambodia and officially recognized the 1863 French protectorate on Cambodia, in exchange for the control of Battambang and Siem Reap provinces which officially became part of Thailand (These provinces would be ceded back to Cambodia by a border treaty between France and Siam in 1906).
France obtained control over northern Vietnam following its victory over China in the Sino-French war (1884-1885). French Indochina was formed in October 1887 from Annam, Tonkin, Cochinchina (which together form modern Vietnam) and the Kingdom of Cambodia following the Sino-French War (1884-1885); Laos was added after the Franco-Siamese War. The federation lasted until 1954. In the four protectorates, the French formally left the local rulers in power, who were the Emperors of Vietnam, Kings of Cambodia, and Kings of Luang Prabang, but in fact gathered all powers in their hands, the local rulers acting only as figureheads.
From 1885 to 1895, Phan Đình Phùng led a rebellion against the colonizing power. Nationalist sentiments intensified in Vietnam, especially during and after World War I, but all the uprisings and tentative efforts failed to obtain any concessions from the French overseers.
Territorial conflict in the Indochinese peninsula for the expansion of French Indochina led to the Franco-Siamese War of 1893. In 1893 the French authorities in Indochina used border disputes, followed by the Paknam naval incident, to provoke a crisis. French gunboats appeared at Bangkok, and demanded the cession of Lao territories east of the Mekong. King Chulalongkorn appealed to the British, but the British minister told the King to settle on whatever terms he could get, and he had no choice but to comply. Britain's only gesture was an agreement with France guaranteeing the integrity of the rest of Siam. In exchange, Siam had to give up its claim to the Tai-speaking Shan region of north-eastern Burma to the British, and cede Laos to France.
The French, however, continued to pressure Siam, and in 1906–1907 they manufactured another crisis. This time Siam had to concede French control of territory on the west bank of the Mekong opposite Luang Prabang and around Champasak in southern Laos, as well as western Cambodia. France also occupied the western part of Chantaburi. In 1904, in order to get back Chantaburi Siam had to give Trat to French Indochina. Trat became part of Thailand again on March 23, 1906 in exchange for many areas east of the Mekong river like Battambang, Siam Nakhon and Sisophon.
In the 1930s, Siam engaged France in a series of talks concerning the repatriation of Siamese provinces held by the French. By 1938, France had agreed to repatriate Angkor Wat, Angkor Thom, Siam Reap, Siam Pang and the associated provinces (approximately 13) to Siam. Meanwhile, Siam took over control of those areas, in anticipation of the upcoming treaty. Signatories from each country were dispatched to Tokyo to sign the treaty repatriating the lost provinces.
On 9 March 1945, with France liberated, Germany in retreat, and the United States ascendant in the Pacific, Japan decided to take complete control of Indochina. The Japanese launched the Second French Indochina Campaign. The Japanese kept power in Indochina until the news of their government's surrender came through in August.
Fighting lasted until March 1954, when the Viet Minh won the decisive victory against French forces at the gruelling Battle of Dien Bien Phu.
The partition was agreed to at the Geneva Conference, where the United States of America, the Soviet Union, the United Kingdom, France and the People's Republic of China also settled a number of outstanding disputes relating to the Korean War. It was at this conference that France relinquished any claim to territory in the Indochinese peninsula. Laos and Cambodia also became independent in 1954, but were both drawn into the Vietnam War.