sentences:  He worked as chief historian of the Japanese Ministry of Finance between 1956 and 1976 and during this period from 1963 to 1965 he was also a research assistant at Harvard University.After resigning his post at the Finance Ministry Hata served as a visiting professor at Princeton University from 1977 to 1978 and then was a history professor at Takushoku University from 1980 to 1993, at Chiba University from 1994 to 1997, and at Nihon University from 1997 to 2002.Hata has been described by numerous historians as an important scholar on the history of modern Japan.