Camille Gorgé was minister (ambassador) of Switzerland in Japan between 1940 and 1945. He was one of the very rare diplomats to have stayed in this country during the war and played a key role to represent the interests of Switzerland and many other countries, including the United States and the United Kingdom. He kept a diary during his stay, which has never been completely published. A copy of the original manuscript, in French, is kept in the Swiss Federal Archives. A Japanese translation has been published in 2023 by Osaka University Press, under the title 『駐日スイス公使が見た第二次世界大戦. This document gives an original perspective on the history of World War II in Japan. It represents unique evidence to understand the daily life of foreigners that stayed in Japan during the war, by personal choice or because their company asked them to do so. It also shows the hard relations with the army and the police, discrimination, imprisonment and the difficulties for a neutral diplomat to fulfill his tasks. Testimonies by foreigners about Japan at war are very rare, and this document is an original and uncompromising contribution to this dark period.