QUICK TIPS FOR USING THIS TOOL:
1. Type a PRESENT-day Place and a HISTORICAL Year or Date, then hit the "Go!" button. The place you type must be a PRESENT-day U.S. city, county, or address*. You can enter a 4-digit year or a date in the format M/D/YYYY. The date can be from the mid-1600s (depending on date of state formation) through 1/1/2000.
2. Historical county boundaries will draw, and an information pane about the county of interest will appear above the map. The information pane lists the historical county name at the red marker, provides details on the latest changes in jurisdiction as of that year, and lists the sources used. TIP: The information pane also lists the full place name in the form of "Place, Historical County, State, USA". To save time, you can highlight the text and Copy (Ctrl+C) and Paste (Ctrl+V) it into your genealogy program's location field.
3. Travel through time and explore the map! Click the < and > buttons next to the Year input box to go back and forward a decade at a time. Zoom in for more detail, then click the map to get information on another location, pan to another state, or type a new place. NEW: You can also check the "Show Research Locations" checkbox and see courthouses, cemeteries, churches, and libraries on the map, which can be clicked on for more information and links about that place. See this post for more information on this functionality.
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* The Place box uses a standard Google Maps geocoding engine, therefore you can type present-day street addresses, road names, points of interest, and the like, and then type in an historical year to see what county that address or road was located in back then (e.g. type "Silver Oaks Cemetery, Tyner, TN" or "Old Lee Highway, Tyner, TN" together with the year 1880). Of course, this doesn't account for addresses or road names that may have changed, so if you suspect that, then just start with the right present-day town or city name.
- This tool works best with Chrome, Firefox, Safari (including iPad), and many other browsers; there are some performance issues with Internet Explorer. For some mobile browsers, click the "View web version" link at the bottom of this page on the mobile browser.
- Occasionally, county lines may take up to 10 seconds to appear; if the county lines never appear, try refreshing the page (F5) and try your search again.
- This tool uses an experimental Google Maps API feature called Fusion Table Layers. The underlying county boundary map files used are quite large, and Google Fusion Tables are themselves a beta product. As with any new and innovative technology, don't be surprised if things occasionally don't function as expected.
- County boundaries must be viewed one state at a time due to states having overlapping claims for the same area in some historical years. To aid in multi-state searches, when you drag the map such that it's center falls in another state, you will be asked if you wish to show county boundaries for that new state instead.
- The fantastic source of the historical county boundaries and related information used in this tool is the Atlas of Historical County Boundaries, a project of The Dr. William M. Scholl Center for American History and Culture at The Newberry Library in Chicago, Illinois. The information is included in this tool under the Creative Commons license shown on the bottom of the linked page.
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