Long ago, this land was all Virginia territory. Then the changes were forced on the people living there, by the encroachment of the people brought in by PENN.
In retrospect I can understand their duress. Virginia law was lower taxes, better government, different church laws, many different aspects to their living in peace verses the laws of the new area of Pennsylvania by Penn. This created an exodus of people out of SW Pennsylvania by 1810 to 1830. Some went as early as 1800 to Ohio and Kentucky mostly. The split between Pennsylvania and Virginia happened in 1779. The rift continued until the 1800's started.
We can jump ahead to the Civil War and then the north west part of Virginia did not agree with the rest of the state over the war, there by causing the split along the ridge or the Allegheny mountains, 1863, creating West Virginia.
Books for research in this region are many, some of the best are in the Library of Virginia and other repositories.
Many societies carry a good amount of information on this region.
Here in is a group of sources for information to learn more.
Virginia Court Records in SW PA by Crumrine,, in part presented by Hermon B Fagley on the PaWashington L Archives.
George K Schweitzer, Ph,ScD - Virginia Genealogical Research
497 Ascot Court
Knoxville, Tenn 37923-5807
Early History of Western Pennsylvania and the Western Campaigns 1754-1853 by Iscrupe, Gentleman of the Bar
The Virginia Genealogist Vol 1, 1967 through Vol, 21, 1977 by John Frederick Dorman published by Heritage Books, Inc,
Heritage Books, Inc, 1340 E Pointer Ridge Place, Bowie, Maryland 20716 great sources for many books,
Pennsylvania Genealogical Research by George K Schweitzer, Ph. ScD same address as above.
Carnegie Library of Pittsburgh,
PA and VA State Archives and their Libraries
Daughters of the American Revolution
Family History Centers ( LDS.org)
The Library of the HIstorical Society of Western Pennsylvania
Sons of the American Revolution
Local libraries resources through out both states.
Genealogical Libraries in both states
Historical Societies in both states.
Never forget to use Google.com or google+
Also try Wiki.com but I worry about the facts on this site.
If facts great if stories be aware. Not right not wrong.
Watch for other service organizations for clues, War of 1812, French Indian Wars, etc.