The Haddorff Piano Company was established by Charles A. Haddorff in 1901 in Rockford, Illinois. The original factory was located at 55 Ethel Street. Haddorff was a large-scale manufacturer, and the firm built pianos for several other prominent piano manufacturers including Bush & Gerts, Clarendon, Bishop, and many others. During the 1920’s the firm was controlled by The Krakauer Brothers Piano Company.

One of Haddorff’s most famous contribution to the piano industry was their introduction of the “Vertichord”, a small upright piano introduced the 1930’s. After World War ll, the Haddorff name was bought by Conn, who shortly thereafter sold the Haddorff name to The Kimball Piano Compay. Kimball discontinued the Haddorff piano brand name around 1960.