World War II: In response to the Japanese occupation of French Indochina, the United States, Britain and the Netherlands freeze all Japanese assets and cut off oil shipments.

French Indochina, officially known as the Indochinese Union and after 1941 as the Indochinese Federation, was a group of French dependent territories in Southeast Asia from 1887 to 1954. It was initially a federation of French colonies (1887–1949), later a confederation of French associated states (1949–1954). It comprised Cambodia, Laos, Guangzhouwan (1898–1945), Cochinchina, and Vietnamese regions of Tonkin and Annam. It was established in 1887 and was dissolved in 1954. In 1949, Vietnam was reunited and it regained Cochinchina. Its capitals were Hanoi (1902–1945) and Saigon.

The ABCD line was a series of embargoes against the Empire of Japan by foreign nations, including the United States, Britain, China, and the Dutch. It was also known as the ABCD encirclement . In 1940, in an effort to discourage Japanese militarism, these nations and others stopped selling iron ore, steel and oil to Japan, denying it the raw materials needed to continue its activities in China and French Indochina. In Japan, the government and nationalists viewed these embargoes as acts of aggression; imported oil made up about 80% of domestic consumption, without which Japan's economy, let alone its military, would grind to a halt. The Japanese media, influenced by military propagandists, began to refer to the embargoes as the "ABCD ("American-British-Chinese-Dutch") encirclement" or "ABCD line".