Onondaga County was formed in 1794 when Herkimer and Tioga Counties ceded land to this new county.

In 1799, Cayuga County was formed from Onondaga County, thereby decreasing the size of Onondaga County by more than one-half.

In 1808, the southern portion of Onondaga County was taken for Cortland County.

In 1816, Oswego County was formed from the northern section of Onondaga County and a portion of Oneida County.

In 1828, Onondaga and Cayuga Counties exchanged land, thereby establishing the current-day Onondaga County boundaries.

28 June 1998
24 October 1999

This Web Page was created by Kim Branagan

-[an error occurred while processing this directive]- person to view the this page since 2 July 1998