Trench warfare
Trench warfare has become archetypically associated with the First World War of 1914–1918, when the Race to the Sea rapidly expanded trench use on the Western Front starting in September 1914. By the end of October 1914 the whole front in Belgium and France had solidified into lines of trenches, which lasted until the last weeks of the war. Mass infantry assaults were futile in the face of artillery fire as well as rapid rifle and machine-gun fire. Both sides concentrated on breaking up enemy attacks and on protecting their own troops by digging deep into the ground. Trench warfare also took place on other fronts, including in Italy and at Gallipoli.
Mường Thanh Valley
The First Indochina War began on December 19, 1946 as a battle between the French trying to regain their colonial claims in Vietnam and the Viet Minh attempting to gain control of the area. In the early 1950s Viet Minh forces were making steady advancements on French-controlled parts of Northern Vietnam. By late 1952 much of the Red River Delta was under Viet Minh control. Due to its proximity to supply routes from China, the Mường Thanh Valley region was vital to the survival and support of the Viet Minh. The French forces in Vietnam under General Henri Navarre sought to occupy Dien Bien Phu. This would allow them to cut off an important supply route to the Viet Minh and also help them to fight against a Viet Minh offensive in Laos.