Pennsylvania was established as a colony in 1681 when the territory was granted to William Penn by King Charles II, of England. Penn, a Quaker with a strong sense of justice, then purchased the land from the native indians. Chester County was founded in 1682, as one of the three original counties in Pennsylvania, along with Philadelphia and Bucks Counties. The name Chester probably suggested by friend of Penn's, Robert Pearson, because it had been the city in England where Pearson resided. Before European settlement, Indians of the Lenni Lenapes tribe were found in the County, but were rapidly displaced by the influx of settlers.
One of the first purchasers of land from Penn was Lancelot Fallowfield. In 1718, a preacher named John Salkield brought a tract of land from Fallowfield. The land extended west from what is now West Bradford Township to the Octorara Creek, and included the area between Upper Oxford and West Caln Townships. Salkield decided to call his land Fallowfield, in honor of its former landowner. Land boundaries were redefined in 1728, when Sadsbury was taken out of the original tract. The courts were unsuccessfully petitioned in 1731 and 1738 to further redefine the tract, but the matter was not accomplished until 1743. The division was along the North Brand of Doe Run, now known as Buck Run, with land west of the creek eventually forming Highland and West Fallowfield Townships. A portion of West Marlborough was subsequently added to the area that had become known as East Fallowfield.