[1] Kiyosawa had a liberal perspective which supported free speech, and as a result most of his diary is dedicated to criticism of the militaristic atmosphere of the Japanese public, the decisions of the military government during the war, and increasing bureaucracy.
He was friends with the fellow liberal journalist Tanzan Ishibashi, who appears several times in his diary entries and who would later become the prime minister of Japan.
In 1919, he switched over to the Chugai Shogyo Simpo newspaper (today known as the Nikkei) and became a writer on foreign affairs, particularly Korea, Manchuria, and China.
[4] In 1943, Kiyosawa founded the Japanese Institute for Diplomatic History (日本外交史研究所) with future prime minister Hitoshi Ashida.
"[4] In 2013, Kiyosawa's daughter Mariko donated the original manuscripts of the Diary of Darkness to Azumino City and its archives.