Official and personal papers of a Quincy, Illinois business executive and patron of the arts. Chairman of the Board of the Quincy Compressor Division of Colt Industries, and Chairman of the Board of the Irwin Paper Company. Founder of the Quincy Symphony Orchestra (1948), first chairman of the Illinois Arts Council (1963-1971), founder and chair of the Associated Councils of the Arts (1962-1972), consultant for the National Endowment for the Arts (1960s-1970s), president of the Quincy Foundation, and active member of Community Arts Councils, Inc.

Contains correspondence, photographs, minutes, publications, clippings, minutes, agendas, financial statements, grant requests, brochures, and newsletters relating to Irwin's involvement in local, state and national arts organizations. Items of interest include material promoting the U.S. Bicentennial in 1976, files on arts activities in Illinois towns and cities in the 1960s, correspondence regarding Irwin's replacement as head of the Illinois Arts Council, material regarding Irwin's activities in the Quincy Foundation and the National Endowment for the Arts, and annual reports from state arts councils in the 1960s and 1970s.