Answer:
Despite heavy U.S. aid, the base was overrun on May 7, 1954.
Step-by-step explanation:
The battle was joined in late 1953 when French forces, who had been rapidly losing ground to the popularly supported Viet Minh, occupied the town of Dien Bien Phu in an attempt to cut the nationalist supply lines into Laos and to maintain a base for forays against enemy forces. Although the Vietnamese quickly cut all the roads into Dien Bien Phu, making it suppliable only by air, the French were confident of their position. They were thus taken by surprise when the Viet Minh Gen. Vo Nguyen Giap surrounded the base with 40,000 men and used heavy artillery to break the French lines.