The Postville Courthouse served the people of Logan County for only eight years, from 1840 until 1848. In the latter year, the people of a nearby town, Mount Pulaski, Illinois, offered to take over the county seat in exchange for building a brick courthouse for the county's use. Concerned about the possibility of a courthouse fire and the destruction of the county's legal records, the county's leaders accepted the offer. The new courthouse, which still survives, is now the Mount Pulaski Courthouse State Historic Site.