At the start of World War II, he left Carleton College and joined the American Field Service where he drove an ambulance for the British Army in Egypt.

[2] Knuepfer completed his studies at Carlton College and received his master's degree in business from University of Chicago.

[1] Knuepfer became involved in local Republican politics as a precinct committeeman and was elected to the Elmhurst City Council.

[7][8] On October 11, 1977, Knuepfer announced that he would run for the Republican nomination for Chairman of the DuPage County Board of Commissioners.

Three days later Republican incumbent Gerald Weeks announced he would not seek reelection and endorse Knuepfer.

[10] In 1990, Knuepfer was an unsuccessful candidate for renomination, losing the Republican primary to attorney Aldo Botti.

[12][13] A through arch bridge that spans the Canadian National Railway tracks in West Chicago, Illinois is named after Knuepfer.