Matsuoka Yosuke was the Japanese Foreign Minister during the early years of the Second World War. It was to Matsuoka that Hitler had made his fateful promise that Germany would back Japan if the Pacific nation found itself at war with the U.S.
Matsuoka was a firm believer in Japan's alliance with Germany—so much so that when the Japanese Foreign Minister was forced out of the cabinet in the summer of 1941 for encouraging Japanese support for German troops in Russia, "Germany lost, for the time being, its best friend" (4.25.41).
Shigenori Togo was the new Japanese Foreign Minister following the military coup. The U.S., through it deciphering of Japanese cables, heard that Togo was planning to issue the U.S. a set of demand for a peace agreement on Japan's terms. The U.S. refused and negotiations between the countries broke down.
Togo was worried that Hitler would demand that Japan join Germany's offensive against Russia; he knew that Japan couldn't take on Russia and the U.S. at once. But Germany backed off on this demand and Japan was able to direct all its resources to attacks on the U.S.
In the winter of 1941, Nomura Kichisaburo served as Japan's ambassador to the U.S., and on behalf of his country attempted to negotiate an understanding between the two nations. Shirer writes that Nomura's desire "to come to an arrangement with America" was genuine, despite the fact that events were swiftly moving beyond his control (4.25.69-70).
Shirer describes Oshima Hiroshi as being "a warrior of a similar cast" as General Tojo Hideki (4.25.75). General Oshima was the Japanese ambassador to Germany during the Second World War, and Shirer describes him as being "a great lover of German-Austrian classical music" (4.25.90). In fact, in the days leading up to the attack on Pearl Harbor, he sent to Austria for a Mozart Festival.
In October 1941, the Japanese government fell in a military coup. The leader of that cabinet was General Tojo Hideki, whom Shirer describes as being "hotheaded," "belligerent," and inclined to "draw closer" to Japan's Axis allies rather than seeking better relations with the U.S. (4.25.75). In his role as Premier during WWII, he directed the bombing of the U.S. at Pearl Harbor, finally plunging the U.S. into the war.