Onondaga County ( /ˈɒnənˈdɑːɡə/ ON-ən-DAH-gə) is a county located in the U.S. state of New York. As of the 2010 census, the population was 467,026. The county seat is Syracuse.

Onondaga County is part of the Syracuse, NY Metropolitan Statistical Area.

The name Onondaga derives from the name of the Native American people who historically lived in the area at the time of European contact, one of the original Five Nations of the Haudenosaunee. They called themselves (autonym) Onoda'gega, sometimes spelled Onontakeka. The word means "People of the Hills." Sometimes the term was Onondagaono ("The People of the Hills"). The federally recognized Onondaga Nation has a reservation of about 9.3 square miles (24 km²) within the county, on which they have self-government.

When counties were established in New York State in 1683, the present Onondaga County was part of Albany County. This was an enormous county, including the northern part of New York State as well as all of the present State of Vermont and, in theory, extending westward to the Pacific Ocean. This county was reduced in size on July 3, 1766 by the creation of Cumberland County, and further on March 16, 1770 by the creation of Gloucester County, both containing territory now in Vermont.

Joanne M. "Joanie" Mahoney (born 1965) is the County Executive of Onondaga County, New York. She is the first woman to hold this position. She took office on Tuesday, January 1, 2008.

Mahoney was raised in Syracuse, New York, as the middle child of nine children [1]. Her father, Bernie Mahoney, was a member of the Syracuse Common Council and then the New York State Assembly. He was also an unsuccessful candidate for Mayor in Syracuse three times [2].

Mahoney attended Shea Middle School and Corcoran High School in Syracuse, then received her undergraduate degree from the Martin J. Whitman School of Management at Syracuse University. Upon completing her undergraduate degree, Mahoney received her law degree from the Syracuse University College of Law.

She is married to Marc Overdyk and has four children.

An attorney by trade, Mahoney previously served as Criminal Prosecutor in the Onondaga County District Attorney's Office. She left work in 1997 to become a full-time stay-at-home mother, but decided to run to serve part time on the Syracuse Common Council [3]. She won election to the Syracuse Common Council in November 1999 and served from 2000 until 2002 [4].

Daniel Benjamin "Dan" Maffei (muff-AY) (born July 4, 1968) is a former U.S. Representative for New York's 25th congressional district, serving from 2009 until 2011, and currently a senior adviser at law firm Manatt, Phelps & Phillips. He is seeking the Democratic nomination to run for his old seat in 2012.

Maffei was born in Syracuse and currently resides in the suburb of DeWitt. He graduated from Nottingham Senior High School in 1986, and continued on to receive a B.A. in history from Brown University in 1990, an M.S. in journalism from the Columbia University Graduate School of Journalism in 1991, and an M.P.P. from the John F. Kennedy School of Government in 1995.

Upon graduating from Columbia, Maffei went to work as a reporter and producer for Syracuse's ABC affiliate WSYR-TV from 1991 to 1993 and part-time reporter for a Watertown news station through 1995.

Prior to his congressional election, Maffei was the Senior Vice President for Corporate Development at consulting firm Pinnacle Capital Management, as well as a frequent guest lecturer at Syracuse University's Maxwell School of Citizenship and Public Affairs and the S.I. Newhouse School of Public Communications.