He also served as Rwanda's Minister of Foreign Affairs from 1969 to 1971. He was also a director at a university.
Personal life and family
Sylvestre Nsanzimana was married. He had 4 children. With his family, they lived for over 10 years in Ethiopia where the children schooled in Lycée Guébré-Mariam and returned to Rwanda. His wife died of illness in 1988. He died in 1999 of illness in Belgium.