From the standpoint of the victorious Allies, the situation in Indochina was ambiguous. Japan was in control and Washington and London viewed France's new leader, General De Gaulle, with suspicion. The Allies divided Indochina at the 16th parallel, and gave the responsibility for accepting the Japanese surrender to nationalist China in the north and to Britain in the south. The British landed a division of the Indian Army under Major General Douglas Gracey at Saigon. He found a Provisional Executive Committee, with a Vietminh minority, nominally in charge and anti-French sentiment running high. Responding to pleas from French inhabitants, Gracey released French troops from Japanese internment and ordered all Vietnamese disarmed. The nationalists responded by calling a general strike. Disorder spread and Gracey used rearmed French troops to help restore order. Cochinchina was plunged into civil war.
In the north, the Vietminh retained control until the appearance of Chinese troops under General Lu Han in mid-September. With American acquiescence, the Chinese kept the interned French troops in detention and systematically looted the economy, manipulating the currency and seizing the Laotian opium crop. Meanwhile the Truman Administration recognized French sovereignty over Indochina, turning away from President Roosevelt's anti-colonialism. The French built up their forces in Saigon, and in October armored units under General Philippe Leclerc broke the Vietminh blockade and began a pacification campaign in the South.
Ho flew to France to negotiate the future of Vietnam, but France was unwilling to recognize independence in any meaningful form; not even the French Communists spoke up in his behalf. The ensuing maneuverings were complex, but the upshot was that Ho, bereft of international support and fearing prolonged Chinese occupation, invited the French back. By April, French had relieved the Chinese in Tonkin and were warily confronting the Vietminh in Hanoi and Haiphong. Negotiations ground on, but to no avail, and tensions increased as both sides prepared for war. What set of the spark is unclear: the Vietminh claimed it was the unwarranted seizure of a Vietnamese fishing vessel in Haiphong harbor on 20 November, 1946, while the French maintained the vessel was transporting arms. However that may be, fighting broke out. The French bombarded Haiphong with heavy loss of civilian life and on 19 December the Vietminh rose against the French. The Vietnam War had begun.
French forces quickly cleared the untrained Vietminh from Hanoi and Haiphong and by March they controlled the cities, the major connecting arteries and most of the productive agricultural land of Vietnam, at least in daylight. In the north, the Vietminh retreated into the wilderness of the Bac Viet where, under the patient eyes of their cadres, they began the slow business of organizing and training for the struggle to come. The overconfident French failed to use the remaining two or three months of dry weather and in so doing missed perhaps their best - and last - chance of victory. With the return of the dry monsoon in October of 1947, the French took the offensive with a vengeance, dropping paratroops into the heart of Vietminh base areas in the Bac Viet. An armored column swept north along the Chinese border and then south from Cao Bang to link up with the paratroops, while a riverine force pressed up the Red River forming the second arm of a giant pincers. Ho and Giap were nearly captured as the paratroops found letters prepared for their signatures still on their desks. From there, things went downhill for the French. The Vietminh put up a dogged resistance, delaying the armored column and forcing the paratroops to fight unassisted for nine days. More importantly, the French failed to draw Giap's forces into a set-piece battle where they could be destroyed; it was the first of many such failures.Page 9 (America in Vietnam)