Answer: France had to surrender after the siege of Dien Bien Phu
Explanation: The Battle of Dien Bien Phu was the final confrontation of the First Indochina War between the French Union's French Far East Expeditionary Corps and Viet Minh communist revolutionaries. It was, from the French view before the event, a set piece battle to expell the Vietnamese and destroy them with superior firepower. The battle occurred between March and May 1954 and culminated in a comprehensive French defeat that influenced negotiations underway at Geneva among several nations over the future of Indochina.