New Horizons Genealogy

"Specializing in New England and New York Colonial American Ancestry"

Onondaga County New York Genealogy and History

Founded: 1794

Named for: Onondaga people

County Seat: Syracuse

Try our genealogy search engine

Search Free Onondaga County New York 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.

Onondaga County, New York 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.

We regret that are unable to do personal research for you. All genealogical and family history records we come across are being added to this website. Please keep checking back.


In 1794, Onondaga County was split off from Herkimer County. This county was larger than the current Onondaga County, including the present Cayuga, Cortland, and part of Oswego Counties.

In 1799, Cayuga County was split off from Onondaga.

In 1808, Cortland County was split off from Onondaga.

In 1816, parts of Oneida and Onondaga Counties were taken to form the new Oswego County.

At the time Onondaga County was organized, it was divided into eleven towns: Homer, Pompey, Manlius, Lysander, Marcellus, Ulysses, Milton, Scipio, Ovid, Aurelius and Romulus.

Free Onondaga County New York Genealogy Records Online

Onondaga County New York Cemetery Records

Onondaga County New York Church Records

Onondaga County New York Cities & Towns

Onondaga County New York Military Records

Onondaga County New York Newspapers

Onondaga County New York Obituaries

Onondaga County New York Wills and Probate Records

Genealogy Research in Onondaga County, New York

Onondaga County Clerk
401 Montgomery St.
Room 200
Syracuse, NY 13202
Phone: (315) 435-2227

Onondaga County Genealogical and Historical Societies

Central New York Genealogical Society
PO Box 104
Colvin Station
Syracuse, New York 13205

New York State Council of Genealogical Organizations
PO Box 2593
Syracuse, New York 13220-2593

Adjacent counties