He later obtained a master's degree in history from the University of Chicago (1920) and a PhD from Harvard.
As a professional historian he published a number of books and articles on American history and also about Japan.
In January 1940 he took up the post of the American Representative of the South Manchurian Railway Company, based in New York.
[2] Akagi died in 1943 [citation needed] and was survived by his wife, Skiza (third daughter of social reformer Abe Isoo[3]), his son Hideya (born Philadelphia), and his daughter Futaba (born New York).
In 1926, he authored a pamphlet for the Japanese Students Christian Association called "The second generation problem: Some suggestions toward its solution."