1800
Beaver County was founded
Beaver County was carved out of Washington and Allegheny Counties in 1800.
1800
Butler County was founded
Butler County, Pennsylvania, was established on March 12, 1800, from a portion of Allegheny County. Like many other Western PA counties, Butler County was named for a Revolutionary War hero, General Richard Butler.
1800
Armstrong County was founded March 12th
1802
Canonsburg became a municipality Feb 22nd
1804
Cranberry became a municipality
1809
Ross Township became a municipality
On June 26, 1809, John McKnight, along with 30 other residents of Pine Township, petitioned the courts of Allegheny for the formation of a new township. In the November term, permission was granted and Ross Township was born. It was called Ross after a prominent Pittsburgh attorney James Ross.