the french reoccupied indochina after the second world war after the territory had been part of the empire of japan. the việt minh launched a rebellion against the french authority. the first few years of the war involved a low-level rural insurgency against french authority. however, after the chinese communists had reached the northern border of vietnam in 1949, the conflict turned into a conventional war between two armies, which had modern weapons supplied by the united states and the soviet union.