[5] The county is named for James Madison, President of the United States and was established on March 1, 1810.

[6] Madison County is part of the Columbus, OH Metropolitan Statistical Area.

[8] In 2008, Madison County, which spans Interstates 70 and 71 as they converge on Columbus, was cited by the Ohio State Highway Patrol as leading the state for the most speeding tickets 20-mph or more over the posted limit.

Three of Madison County's 18 fatal crashes in 2006 and 2007 occurred on interstates.

[11] Madison County is also home to the Ohio Peace Officer Training Academy, the Ohio Bureau of Criminal Identification & Investigation, and several prison facilities.

22.30% of all households were made up of individuals, and 9.50% had someone living alone who was 65 years of age or older.

As of the 2010 United States Census, there were 43,435 people, 14,734 households, and 10,580 families living in the county.

The only two Democrats to win the county were Franklin D. Roosevelt in 1932 & 1936 and Lyndon B. Johnson in 1964.

School districts include:[25] The following libraries serve the communities of Madison County.