World War II: The People's Army of Vietnam is formed to resist Japanese occupation of Indochina, now Vietnam.

The People's Army of Vietnam (PAVN), officially the Vietnam People's Army, also recognized as the Vietnamese Army, the People's Army or colloquially the Troops, is the national military force of the Socialist Republic of Vietnam and the armed wing of the ruling Communist Party of Vietnam (CPV). The PAVN is the backbone component of the Vietnam People's Armed Forces and includes: Ground Force, Navy, Air Force, Border Guard and Coast Guard. Vietnam does not have a separate and formally-structured Ground Force or Army service. Instead, all ground troops, army corps, military districts and special forces are designated under the umbrella term combined arms and belong to the Ministry of National Defence, directly under the command of the CPV Central Military Commission, the Minister of National Defence, and the General Staff of the Vietnam People's Army. The military flag of the PAVN is the National flag of the Socialist Republic of Vietnam defaced with the motto Quyết thắng added in yellow at the canton.

In mid-1940, Nazi Germany rapidly defeated the French Third Republic, and the colonial administration of French Indochina passed to the French State. Many concessions were granted to the Empire of Japan, such as the use of ports, airfields, and railroads. Japanese troops first entered parts of Indochina in September 1940, and by July 1941 Japan had extended its control over the whole of French Indochina. The United States, concerned by Japanese expansion, started putting embargoes on exports of steel and oil to Japan from July 1940. The desire to escape these embargoes and to become self-sufficient in resources ultimately contributed to Japan's decision to attack on December 7, 1941, the British Empire and simultaneously the United States. This led to the United States declaring war against Japan on December 8, 1941. The United States then joined the side of the British Empire, at war with Germany since 1939, and its existing allies in the fight against the Axis powers.

Vietnam, officially the Socialist Republic of Vietnam (SRV), is a country at the eastern edge of mainland Southeast Asia, with an area of about 331,000 square kilometres (128,000 sq mi) and a population of over 100 million, making it the world's fifteenth-most populous country. One of two communist states in Southeast Asia, Vietnam shares land borders with China to the north, and Laos and Cambodia to the west. Its capital is Hanoi and its largest city is Ho Chi Minh City.