The American Historical Society of Chicago was not an organization but a commercial publisher (with a misleading name) specializing in subscription and sponsored works of local history and biography. They were competitors of Goodspeed Publishing Co. and Lewis Publishing Co., both also of Chicago. In this type of publication, editing and fact-checking was minimal to non-existent, so assertions regarding ancestors and earlier generations by biographees should be viewed with caution.
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Vols. 1-2 consist of a history of Kentucky in 80 chapters, from earliest exploration to after the Civil War.
Vols. 2-5 consist of biographical sketches in no discernible order, either alphabetical or geographical.