1781
Washington County was founded March 28th
On March 28, 1781, Washington County was created by an act of the Pennsylvania General Assembly, and named in honor of General George Washington.
1781
Peters Township became a municipality
1781
Washington & Jefferson College was founded
1783
Fayette County was founded Sept 26th
The county was created on September 26, 1783, from part of Westmoreland County and named after the Marquis de Lafayette.
1785
Brownsville became a municipality
1787
University of Pittsburgh was founded Feb 28th
1788
Allegheny County was established
Created on September 24, 1788, from parts of Westmoreland and Washington Counties and named for the Allegheny River.
1788
Upper St. Clair became a municipality
1788
Plum became a municipality
1788
Moon became a municpality