Oskaloosa Public Library
Carnegie Grant Information
Town & County
Twelfth Census of the United States — 1900. p. 450.
Oskaloosa is the county seat of Mahaska County, which was established on February 17, 1843. The county was named in honor of Chief Mahaska of the Ioway Tribe. In 1844, the county seat was located at Oskaloosa.
(Source: Pratt, LeRoy G. “The Counties and Courthouses of Iowa.” Mason City, Ia; Klipto Printing & Office Supply Company, 1977, p. 216.)