Thomas C. Mathieu was born on December 2, 1936 in Sheboygan, Wisconsin to Clement and Florence Mathieu. The Mathieu family moved to Grand Rapids in the early 1940s and lived on the West Side. They later moved to a 40-acre farm on Knapp Street in Grand Rapids Township. After graduating from Catholic Central High School in 1954, Mathieu briefly attended Aquinas College. He left school to work at Leitelt Iron Works, where he became involved in the United Auto Workers union. Mathieu was elected Vice President of the Kent County Labor Council, was assistant to the editor of the Grand Valley Labor News and was awarded Labor's Man of the Year award in 1968.

Beginning in the 1960s, Mathieu was active in the West Side Advisory Council. He became director of the West Side Complex and in 1971 was promoted to Director of Community Development for the Kent Community Action Program. He resigned from that position on June 1, 1974 to run for State Representative in the 92nd district.

Mathieu served as a legislator in the Michigan State House of Representatives from 1975 through 1998. Mathieu was active during his time in the House and was involved in numerous bills, including the Elliot-Larsen Civil Rights Act (1976), the Mathieu-Gast Home Improvement Act (1978), the Home Heating Assistance Act, the Senior Prescription Drug Program and the Long Term Care Ombudsman Act.

Mathieu helped to secure funding for a number of local organizations, including the Ford Presidential Museum, the Michigan Veterans Facility, the Grand Valley State University Eberhard Center, the Grand Rapids Art Museum and the Grand Rapids Public Museum. Mathieu was involved with community colleges across the state, and especially Grand Rapids Junior College (later Grand Rapids Community College). He also played a vital role in the reinstatement of the Michigan Civilian Conservation Corps program and the establishment of the Michigan CCC Museum.

For more information about Mathieu, see his autobiography,“An Impelling Desire to Serve,” (Box 10 Folder 12)