Fact File : Declaration of War on Japan
8 December 1941
General Töjö (Japanese Minister for War and Prime Minister from 1941-44), Stalin, Churchill, Roosevelt, Cordell Hull (US Secretary of State), Admiral Yamamoto, Matsuoka Yösuke (Japan's foreign minister).
Outcome: Britain at war with Japan.
A New York newspaper announces the outbreak of war between America and Japan©
For four years, Japan's designs on China had caused alarm to the Allies. By 1938 Japan occupied a vast area of the Chinese coastline. Japan's ambition was to establish Japanese primacy in Asia and incorporate China into the Empire, subduing any opposing Western nation.
On 27 September 1940, Japan signed the Tripartite Pact with Germany and Italy, binding the three countries to mutual support. Japan now faced a war with Russia and Hitler's attack there in June 1941 came as a disturbing surprise to the Japanese. A Russo-Japanese non-aggression pact was negotiated by Matsuoka Yösuke, Japan's foreign minister, in 1941 - but Stalin would eventually break the terms of this agreement.
Most pressing, however, was the American threat to Japan's expansion southward. American intelligence infiltrated Japanese diplomatic ciphers and acted decisively with economic warfare, placing embargoes on Western trade with Japan. Japan responded with negotiations as they deliberated over war.
By 5 November 1941, Töjö had decided that Japan did not wish to become a 'third-class nation within two or three years' and resolved that 25 November was the deadline for accepting American concessions. US intelligence had forewarnings of war, but considered the Philippines most vulnerable.
Japan declared war against the Allies on 7 December 1941, and Britain announced the war the following day. An imperial rescript accompanied Japan's declaration of war, reading:
'It has been truly unavoidable ... Eager for the realisation of their inordinate ambition to dominate the Orient, both America and Britain, giving support to the Chungking regime [in China], have aggravated the disturbances of East Asia. Moreover these two powers, inducing other countries to follow suit, have increased military preparations on all sides of our empire to challenge us.'
The lengthy declaration was transmitted on Sunday 7 December 1941, but a pre-emptive attack (organised by Admiral Yamamoto) on the US Pacific Fleet's base in Hawaii - Pearl Harbor - was already under way.
The fact files in this timeline were commissioned by the BBC in June 2003 and September 2005. Find out more about the authors who wrote them.