Map Guide To The U.S. Federal Census: 1790-1920
by William Thorndale and William Dollarhide

Genealogical research in U.S. censuses begins with identifying correct county jurisdictions. On each of the nearly 400 maps in this book, the old county lines are superimposed over the modern ones to highlight the boundary changes at 10-year intervals.

Accompanying each map are explanations of boundary changes, notes about the census, and locality-finding keys, plus much more. There is an index, which lists all present-day counties, plus nearly all-defunct counties, or counties that have been renamed. In short, this is the most complete list of American counties ever published.

445 pp., paperback, 1991, ISBN 0-8063-1188-6