Note: This article originally appeared in the December 2003 issue of IGS Newsletter and was updated and expanded by the author in July 2007.
Knox County was not always the size it is now. In fact, it was only in 1842-43 that its boundaries were fixed for the thirteenth and final time. So depending on when your ancestor settled in Indiana, they could have been living in Knox County.
Knox County was formed by proclamation on June 20, 1790. It was only the second county formed from the Northwest Territory. At the time of the county's formation, its southern boundary was the Ohio River and its northern boundary was Lake Superior.
The eastern and western boundaries were a little more complex. The eastern boundary started at the mouth of the Great Miami River, followed the river north to Ft. Laramie (about 45 miles north of present-day Dayton, Ohio), then due north. The western boundary started at the mouth of the stream near Ft. Massac (between Metropolis, Illinois and Paducah, Kentucky), angled northwest to where the Little Michilmacinack (Mackinaw) River met the Illinois River (south of Peoria, Illinois), followed the Illinois River to where it meets the Des Plaines (Chicago) River and the Theokiki (Kankakee) River, then due north to the northern boundary of the United States.
This meant that at one time, Knox County included all of Indiana, half of Illinois, a little of the west side of Ohio, half of Lower Michigan, most of Upper Michigan, and a little of the east side of Wisconsin!
But that began to change. On August 15, 1796, all of the Illinois area north of the Des Plaines/Chicago River and all of the Wisconsin area were given to St. Clair County (Belleville IL). A line was drawn from the southernmost point of Lake Michigan to Ft. Wayne, to the portage between the St. Mary's River and the Miami River. The land north of this line became Wayne County (Detroit MI).
"The Gore" is the part of Indiana east of the Greenville Treaty Line and west of the First Principal Meridian (a survey line). The Greenville Treaty Line went from the mouth of the Kentucky River to Fort Recovery. On June 22, 1798, the area of The Gore was taken from Knox County and given to Hamilton County (Cincinnati OH).
When the Indiana Territory was officially formed from the Northwest Territory, Knox County's boundaries were again changed. On February 3, 1801, Clark County (Jeffersonville IN) was formed from the eastern side of Knox County. The border between the two counties was marked from the mouth of the Blue River (near Leavenworth) following the river to the Vincennes-Clarkesville Rd. (today known as Old U.S.150), then due north to the East Fork of the White River, following this river to its headwaters near Ft. Recovery. The western boundary of the county started at the Great Cave on the Ohio River (near Cave-in-Rock, Illinois) and went due north along the edge of Randolph County, then angled north-northeast to the southernmost point of Lake Michigan.
This put part of what is now Lake County, Indiana, into St. Clair County, Illinois Territory. The northern boundary became a diagonal line between the point where the Great Kennoumic (Calumet) River met the southernmost point of Lake Michigan.
On April 20, 1802, the boundary between the Indiana Territory and the Ohio Territory was changed to a line due north from the mouth of the Great Miami River. This put The Gore in Clark County, Indiana. It also moved the eastern boundary a few miles west of Ft. Recovery. The boundary now coincided with the First Principal Meridian.
On January 25, 1803, when Ohio became a state, the northern boundary was changed to an east-west line passing through the southern tip of Lake Michigan. This put part of what are today the northern counties of Indiana into Wayne County, Indiana Territory, which became Wayne County, Michigan Territory in 1805.
On October 11, 1808, Harrison County was created. This moved the southern part of the eastern border of Knox County to the Second Principal Meridian from the Ohio River to the Indian boundary line created by the Grouseland Treaty in 1805. (Roughly from the Perry County/Crawford County line at the Ohio River north along SR37 to the East Fork of the White River at Bedford.)
On February 3, 1809 the Illinois Territory was created. The new western boundary for Knox County was the Wabash River from the Ohio River to Vincennes, then due north along the current state line until about Newton County, where it angled northeast to the southernmost point of Lake Michigan.
On November 27, 1810, Wayne County (Richmond IN) was created on the east side of the Indiana Territory. This only removed a small amount of territory from Knox County.
Then on March 9, 1813, the southern boundary was changed to the White River. The land south of the river became Gibson and Warrick counties.
Washington County was extended on September 1, 1814, taking a triangle of land from Knox County. The western line of Washington County went due north along the Second Principal Meridian until it met the line formed by the Treaty of Grouseland, then followed the treaty line southeast to the Knox County boundary (East Fork of the White River).
On December 26, 1815, the eastern boundary (the portion along the Second Principal Meridian) was moved two miles west, and Orange County was created. This line again went north to the Treaty of Grouseland line, and southeast to the East Fork of the White River.
Indiana became a state December 11, 1816. On December 30, 1816, Sullivan County (Sullivan IN) was created (effective January 15, 1817). It encompassed the all land north of the line dividing congressional townships five and six from the Wabash River to the White River and south of the Indian Treaty Line of 1809. Knox County covered only the area of the modern-day counties of Knox, Daviess, Martin, and part of Greene. It was this size for only a month. On December 24, 1816 a law was passed creating Daviess County (effective February 15, 1817). The boundary between Knox and Daviess counties was the West Fork of the White River. The part of the previous Knox County north of the Indian Treaty Line (Fort Wayne 1809) became Unorganized Territory controlled by the State of Indiana.
The final boundary charge for Knox County didn't occur until the 1842-43 legislature. It straightened the line between Sullivan County and Knox County next to the Wabash River. Knox County only lost about three square miles.
The McGrady-Brockman House is the location of many records of Knox County. A division of the Knox County Public Library, 502 North Seventh St., Vincennes IN 47591, it is on the corner of Seventh St. and Hart St. across from the library. The Knox County Indiana Regional Historical and Genealogical Collection combines the records from the Knox County Public Library Historical Collection, the Knox County Records Library, the Francis Vigo Chapter DAR Library, and the genealogical records from the Byron R. Lewis Historical Library of Vincennes University. Check their website (http://www.kcpl.lib.in.us) for more information.
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