Top Secret: Combined Fleet Operation Order No 1

5th November 1941: An Imperial Conference in Japan decides to issue the order for an attack on the United States Pacific Fleet

Tensions between the United States and Japan had been mounting all year, with the US demanding that Japan should withdraw from China. Although negotiations would continue for the rest of November, the two sides were far apart and there seemed little realistic prospect of them coming to an agreement.

Yamamoto onboard the battleship Nagato in 1940

Admiral Y…