In 1899 Col. Frank M. Thorpe started F.M. Thorpe Manufacturing Co. as a part-time operation in a small barn in Lamar, MO. Col. Thorpe's first product was a hand-made wire scoop used in grocery stores to scoop dirty potatoes from burlap bags. By 1920, the business had grown into a full-time operation with Col. Thorpe's son, Frank C. joining him in 1927.

In 1930, the business moved to the Lamar Milling Co. building which still stands today. Thorco's offices remained in this building until a new corporate headquarters was constructed in 1992.

James Allen and Kenneth Howard purchased the business from Frank C. Thorpe, the founder's son, in 1966. By mid 1967 the partnership had adopted the tradename THORCO, an updated derivative of FM Thorpe Manufacturing Co. From 1967 through 1984 under their leadership, the company experienced unprecedented growth in both employees and manufacturing facilities.

In 1984 the company was sold to Kansas City business men, Ed Benson and Don Alexander. This partnership continued to focus on growth and expansion until 1990, when Thorco was acquired by the current owner, The Marmon Group of companies headquartered in Chicago, Illinois.

The Marmon Group of companies is an international association of autonomous manufacturing and service companies with collective sales in excess of $7 billion.