[The account below is partial and still under construction]
Anthony (n.d.: 39) reports as follows:
Charles Carpenter Fries spent most of academic career at the University of Michigan. He was 'part of the mainstream of American language study; a member of the Linguistic Society of America from its beginning, once its president, more than once Director of its Linguistic Institutes; member of the [. . .] National Council of Teachers of English, and once its president; and a supporter and vice president of the Modern Language Association'. His students included Robert Lado and Kenneth Pike. (Anthony n.d.: 39)
Fries was primarily a linguist specializing in the English language, but he was always concerned with how languages could best be taught and learned. Early on in his career he was interested in improving the ways English was taught to native speakers, and later on English as a second language. According to Anthony (ibid.), it is no accident that the American TESOL Organisation chose Michigan-trained people for many of its early presidents.
Sources (most not yet incorporated into the above account):
Anthony, Edward M. 1968. 'Charles Carpenter Fries 1887-1967'. English Language Teaching 23/1: 3-4; Fries, Peter Howard and Fries, Nancy M. (eds). 1985. Toward an Understanding of Language: Charles Carpenter Fries in Perspective, Amsterdam: Benjamins (in particular, 'Bibliography of Charles C. Fries' and Bailey, Richard W, 'Charles C. Fries: The life of a linguist'); Anthony, Edward M. n.d. [1986?]. 'The work of Charles Fries within the changing contexts of language teacher education', in Bickley, Verner (ed.), Future Directions in English Language Teacher Education: Asia and Pacific Perspectives, Hong Kong: Institute of Language in Education, Education Department; Norris, William E. and Strain, Jeris E. (eds). 1989. Charles Carpenter Fries: His 'Oral Approach' for Teaching and Learning Foreign Languages. Washington, D.C.: Georgetown University Press.