The document provides background on WWII and Japan's involvement. It discusses how Japan invaded China and tried to invade Russia after facing economic problems. It also explains how Japanese officials in Korea were targeted as Japan started losing WWII. Additionally, it covers Pearl Harbor and kamikaze pilots who willingly crashed planes into US battleships, viewing it as an honorable death. Finally, it notes that while Japan seemed to be winning in Korea at first, they ultimately lost WWII, leading many Koreans to oppose Japanese rule in their country and marking the start of the Korean-Japanese conflict addressed in the book.