Hello All,

An excellent website for determining county boundary changes is found at:
http://www.maps.n2genealogy.com/

The section on County & State Maps "contains rotating animated maps showing all of the county boundary changes & all of the county boundries for each census year for each year over layed with past and present maps so you can see the changes in county boundries."

The animated maps indicate which year a county was chartered and the parent county(s) from which it was derived.

This site is a great tool for studying U.S. State and County Boundry Maps and much more.

Art Thomas