1790 Illinois County Formation Map
Try our genealogy search engine
1790--ST. CLAIR AND KNOX
As Counties of the North West Territory
April 27--County of ST. CLAIR set off as follows: Beginning at the mouth of the little Michilmacinack River, running thence southerly in a direct line to the mouth of the little river above Fort Massac, on the Ohio River; thence with the Ohio to its junction with the Mississippi; thence with the Mississippi to the mouth of the Illinois River to the place of beginning with all the adjacent Islands of the said Illinois and Mississippi Rivers. St. Clair County divided into three judicial districts, viz.: Cahokia, Prairie du Rocher and Kaskaskia; in each of which sessions of the several courts should be held during the year in the same manner as if each district represented a distinct county.
[Territorial Records of the Northwest Territory, St. Clair Papers, volume 2, page 165.]
June 20--A county named Knox was laid off with the following boundaries: Beginning at the Standing Stone Forks of the Great Miami River and down the said river to the confluence with the Ohio River; thence with the Ohio River to the small stream or rivulet above Fort Massac; thence with the eastern line of St. Clair County to the mouth of the Little Michilmacinack; thence up the Illinois River to the forks to the forks or confluence of the [Theokiki] and Chicago [DesPlaines]; thence by a line to be drawn due north to the boundary of the Territory of the United States, and so far easterly upon said boundary line as that a due south line may be drawn to the place of beginning.
[Territorial Records of the Northwest Territory, St. Clair Papers, volume 2, page 166.]