Sewatson on Family Tree Circles

Strong evidence of the Watson migration from England to Pennsylvania is found in many documents. Many parts of Pennsylvania had settlements of Watson's, but Lancaster, Pennsylvania is where my family roots are from. Eventually, members of my family settled in Brown, County, Ohio. How and why they settled in that region is a bit of a mystery. I have yet to find published documents of why they left the Pennsylvania area. Was it because of the Revolutionary War? Perhaps the Civil War? I am actively searching for information to prove this theory.