Robert G. Crist
In 1750, Pennsylvania west of the main stem of the Susquehanna River, except York County and its future offspring, Adams, became the new county of Cumberland. However, during the Revolutionary era Cumberland lost two-thirds of its territory. First, in 1771 the province sliced off fourteen townships from the western end and erected Bedford County. Then it created Westmoreland County from Bedford in 1773. By 1776, Cumberland County was reduced to twenty-three townships. Westmoreland five years later lost its western end when Washington County came into being on its southern flank in 1781 and when Fayette was created in 1783. Accordingly, by 1783 four county seats covered the Cumberland County of twenty years earlier.
The entire province was said to have had a population of 220,000 in 1755,1