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Understanding Boundary Changes
by Mary Lou Bevers

Did you know that counties have genealogies? Some only had one parent, while others had as many as three or four (partial) parents? Many had "children."

Before you can do effective research in a specific locality, you must first learn what jurisdiction (county and state) that spot was in during your time period of interest, so you know which county's records might contain information about your ancestors.

Large, original counties were divided to form new counties. Generally, records up to the time of the split would be kept in the old/parent county, and the new county would begin keeping records of its own.

Your ancestors may have lived in one spot for many, many years--yet lived in four or five different counties--and therefore, appear in records of all of those counties.

So, how do you learn the things you need to prepare you for research? There are three very important books that contain the information you need to study to determine the background facts for each county.

One is Ancestry's Redbook (revised edition), available in most library genealogy collections, and available for purchase from Ancestry. It is a state by state listing of all current (and discontinued) counties in the U.S. It tells when each county was organized and from what parent county/coutnies. You just keep working back through the parent counties into the appropriate time period. This book also indicates the earliest records still existing in each record category for each county. It also identifies the county seat and has excellent maps defining every county, plus bordering counties, even in the surrounding states. This is a very valuable tool. Every researcher should own a copy of this book to refer to often.

Another "must have" book is Map Guide to the U.S. Federal Census 1790-1920, by William Thorndale and William Dollarhide, published by Genealogical Publishing Company. It is a book of maps with county boundaries within each state for every census decade. It helps you to see boundaries in an entirely different light. For example, Ohio County, Kentucky came all the way to the Ohio River in 1810, as did Knox County, Indiana; therefore, some residents of these counties (maybe your ancestor's families) lived just across the river from each other. Think how far apart these counties are today! Consider the boundaries of these big, old counties when researching for families "nearby."

If your ancestor suddenly disappeared from a county's records, check to see if a new county had been formed about that time. Maybe their homeplace was in what is now the new county. A book titled Encyclopedia of Local History and Genealogy, U.S. Counties published by AIS is a quick reference for determining progeny counties.

It is essential that you study the records and interpret them carefully in order not to miss important information.

A person said to have been born in 1785 in Virginia may have actually been born in what is now Kentucky, but was Virginia in 1785. Mary Jones, born about 1788 in Virginia may be the same person as Mrs. Molly Smith, born about 1790 in "Kentucky."

As Indiana was settled, it underwent fewer county splits than some of the other states. Except for a few boundary relocations, Indiana counties were the same in 1840 as they are today, other than the formation of Howard and Tipton counties in 1844 and Newton County (established in 1835, abolished in 1839, and re-created in 1859). Most counties in the southern third of Indiana were organized by 1820, and therefore there are fewer years to search in parent county records for this region.

Some other states are now as simple to understand. For example, if your ancestor was in Keyser, Mineral County, West Virginia in the 1870 census, and the family had lived there for many years, then you would need to know this:
--Mineral County, West Virginia was organized in 1866 from Hampshire County, Virginia/West Virginia;
--Hampshire County, Virginia was organized in 1754 from Frederick and Augusta counties, Virginia;
--Frederick County was organized in 1743 from Orange County, Virginia;
--Augusta County was organized in 1745 from Orange County, Virginia;
--Orange County was organized in 1734 from Spotsylvania County, Virginia;
--Spotsylvania County was organized in 1721 from Essex, King & Queen, and King William counties, Virginia; and so it goes--back in the early 1600's

Earlier records for present-day Mineral County, West Virginia would be found in the following counties:
1721-1734 Spotsylvania County, Virginia
1734-1743 Orange County, Virginia
1743-1754 Frederick County, Virginia
1754-1865 Hampshire County, Virginia/West Virginia
1866-present Mineral County, West Virginia

Some counties in the U.S. are only a county or two away from multiple states. An example is the narrow arm of Maryland. In addition to Maryland counties, you might need to check nearby counties in Pennsylvania, West Virginia and Virginia.

If records are not found where you think they should be, then always try surrounding counties. In order to do this, you have to learn what the surrounding counties were at that time. Studying these three books will help you understand the appropriate counties to check.