[2] Jo Daviess County is part of the Tri-State Area and is located near Dubuque, Iowa and Platteville, Wisconsin.

As part of the Driftless Area, Jo Daviess County contains rugged terrain compared to the rest of the state.

It is named for Maj. Joseph Hamilton Daveiss, United States District Attorney for Kentucky, who was killed in 1811 at the Battle of Tippecanoe.

The end of the Black Hawk War led to an additional surge of immigration, once again coming almost exclusively from the six New England states as a result of overpopulation combined with land shortages in that region.

These settlers were primarily members of the Congregational Church though due to the Second Great Awakening many of them had converted to Methodism and some had become Baptists before coming to what is now Jo Daviess County.

As a result of this heritage the vast majority of inhabitants in Jo Daviess County, much like antebellum New England were overwhelmingly in favor of the abolitionist movement during the decades leading up to the Civil War.

Several areas are protected by the charitable organization Jo Daviess Conservation Foundation:[13] As of the 2010 United States census, there were 22,678 people, 9,753 households, and 6,514 families residing in the county.

It voted Democratic only four times between 1856 and 1992: for Grover Cleveland in 1892, Woodrow Wilson in 1912, Franklin D. Roosevelt in 1932, and Lyndon B. Johnson in 1964.