I just saw the 1965 film 317th Platoon, about a French-led Cambodian platoon ordered to retreat in 1954, while the siege of Dien Bien Phu was underway. It is playing in New York City through Wednesday. Harrowing, well photographed and well-acted, I highly recommend it.
http://metrograph.com/film/film/1599/the-317th-platoonThe writer/director was captured at Dien Bien Phu.