Victory at Dien Bien Phu, May 7, 1954 On May 7, 1954 General Giáp ordered the final assault on the French imperial troops at Dien Bien Phu. The day ended in total victory over the French forces after nearly 2 months of siege and battle. It was a decisive victory for the Vietnamese freedom fighters and such a crushing blow for the French that it ultimately led to the final departure of all French troops from Vietnam in 1956.