Duggan was educated at the
College of the City of New York (CCNY) where, after completing his undergraduate and some graduate work in 1896, he began teaching while pursuing graduate studies at
Columbia University, where he received a
Ph.D. in 1902. He was a professor of
diplomatic history and later the history of education at CCNY, and became head of the education department in 1906. Duggan founded
The Institute of International Education in 1919, together with Nobel Laureates
Elihu Root and
Nicholas Murray Butler, and was the first director, serving until 1946. He was a director of the
Council on Foreign Relations during 1921–1950. Duggan was married to Sarah Alice Elsesser, who was a director of the Negro Welfare League of
White Plains, New York. == Works ==