New Horizons Genealogy

"Specializing in New England and Allegheny Colonial American Ancestry"

Allegheny County Pennsylvania Genealogy and History

Founded: September 24, 1788

Named for: Allegheny River

County Seat: Pittsburgh

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Search Free Allegheny County Pennsylvania Genealogy and Family History Records Online including census, cemetery, vital, military and other genealogical and historical records that can be used for your family history research.

Allegheny County, Pennsylvania genealogy and family history page is a place where you can come in and research your genealogy and family history. We also do our best to provide a history of the area, to provide you with an overview of the time in which your ancestors lived.

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Allegheny County was officially created on September 24, 1788, from parts of Washington and Westmoreland counties. It was formed to respond to pressure from the increase in settlers living in the area around Pittsburgh; this was designated as the county seat in 1791. The county originally extended north to the shores of Lake Erie; it was reduced to its current borders by 1800. As population increased in the territory, other counties were organized.

Free Allegheny County pennsylvania Genealogy Records Online

Allegheny County Pennsylvania Military Records

Allegheny County Pennsylvania Tax Lists

Adjacent Counties