Jo Daviess County was formed in 1827 out of
Henry and
Putnam counties. It is named for Maj.
Joseph Hamilton Daveiss,
United States Attorney for
Kentucky, who was killed in 1811 at the
Battle of Tippecanoe. The local pronunciation is "Davis". Jo Daviess County was founded exclusively by immigrants from
New England. These were old stock "
Yankee" immigrants, meaning they were descended from the English
Puritans who settled New England in the 1600s. The completion of the
Erie Canal caused a surge in New England immigration to what was then the
Northwest Territory. 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. Some of these later settlers were from
upstate New York and had parents who had moved to that region from
New England shortly after the
Revolutionary War. New Englanders and New England transplants from upstate New York were the vast majority of Jo Daviess County's inhabitants during the first several decades of its history. 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. The Congregational Church subsequently went through many divisions and some factions, including those in Jo Daviess County that affiliated with the
Church of Christ and the
United Church of Christ. 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. In the late 1880s and early 1890s
Irish and
German migrants began moving into Jo Daviess County, most of these later immigrants did not move directly from
Ireland and
Germany, but rather from other areas in the
Midwest where they had been living, particularly the state of
Ohio.
County border changes • 1830The northern border of Illinois and Wisconsin was formally established. Until that time, several Wisconsin towns actually were under the jurisdiction of Jo Daviess County. • 1831
Rock Island County was formed from a part of the county, along with a new northern extension of Henry County and Putnam County. • 1836
Whiteside,
Ogle, and
Winnebago counties were formed from the southern and eastern sections of the county. • 1837
Stephenson County was formed from the eastern section of the county. • 1839
Carroll County was formed from the southern section of the county. File:Jo Daviess County Illinois 1827.png|Jo Daviess County at the time of its creation to 1831 (Wisconsin border adjustment not shown) File:Jo Daviess County Illinois 1831.png|Jo Daviess between 1831 and 1836 File:Jo Daviess County Illinois 1836.png|Jo Daviess between 1836 and 1837. Whiteside and Ogle counties remained temporarily attached to Jo Daviess until county governments could be organized. File:Jo Daviess County Illinois 1837.png|Jo Daviess between 1837 and 1839 File:Jo Daviess Counry Illinois 1839.png|Jo Daviess reduced to its current size in 1839 by the creation of Carroll County and the organization of a government in Whiteside County ==Geography==