From R. S. Dills' History of Fayette County
ORGANIZATION AND BOUNDARY
Thoroughly to comprehend the institution and boundary of Fayette, it will be necessary to trace the territory from which it was taken.
July 27, 1788, Washington County was formed under the territorial government, and included all that part of Ohio east of a line drawn from Cleveland, up the Cuyahoga, down the Tuscarawas thence west to the road from the Shawanoes town on the Scioto to Sandusky; thence south to and down the Scioto to its mouth.
January 2, 1790, Hamilton was organized, embracing the territory between the two Miamis, as far north from the Ohio as the "standing stone forks" of the Big Miami. June 22, 1798, it was changed so as to include all that part of Indiana lying between the Greenville treaty line, and the western line of Ohio, and all that part of Ohio west of the Little Miami, to the lower Shawanoes towns on the Scioto, and extending north to the southern line of Wayne.
The county of Wayne originally began at the Cuyahoga, ran up that river and down the Tuscarawas to the portage above Ft. Lawrence; thence west to the east line of Hamilton; thence west, northerly to the portage of the Miami and St. Marys; thence west, northerly, to the portage of the Wabash and Maumee, where Ft. Wayne now is, extending to the southern point of Lake Michigan; thence along its western shore to the northwest part; thence north to the territorial boundary in Lake Superior, and with the said boundary through lakes Huron, Sinclair, and Erie, to the place of beginning.
Ross County was established August 20, 1792. "Beginning at the forty-second mile tree, on the line of the original grant of land by the United States to the Ohio Company, which line was run by Israel Ludlow." This "forty-second mile tree" was forty miles almost due north from Pomeroy, on the Ohio River, and a little distance southwest from Athens, in Athens County. From this point it extended west into the western part of what is now Highland County, about ten miles southwest from Hillsboro; thence north to the southern boundary line of Wayne County, described above; thence east on said line, to a point on the present southern boundary line of Wayne County, almost due south from Wooster, and a very little east of the eighty-second meridiian west longitude; thence south to the place of beginning. The eighty-second meridian west from Greenwich is perhaps not more than a mile west of the original eastern line of Ross County.
It will be observed that the original east line of Hamilton was the Little Miami. Yet in the description of Wayne we find the words: "thence by a west line to the eastern boundary of Hamilton" ("which is a due north line from the lower Shawanoes towns on the Scioto"). Also, that a portion of Hamilton, beginning at the mouth of Eagle Creek, was attached to Adams.
Highland County originally began at the twenty mile tree, due north from the mouth of Elk Creek, on the Ohio; ran east twelve miles; then northeastwardly to the eighteen mile tree from the Scioto, at the intersection of Ross, Clermont, and Adams lines "thence to the mouth of the rocky fork of Paint Creek; thence up main Paint to the south line of Franklin County (now Pickaway); thence with said line west to the east line of Greene County, thence with said line south to the southeast corner of the same; thence with the south line west, to the northeast corner of Clermont (certainly Warren); and from the beginning west to the north fork of White Oak Creek; thence north to the line of Warren County; thence with said line east to corner of Clermont and Warren." (This description is vague.)
Fayette was formed January 19, 1810,—took effect March 1st,— from Ross and Highland. Beginning at the southwest corner of Pickaway, running north "with the line of said county to the corner of Madison; thence west with said line to the line of Greene County; thence south with Greene County to the southeast corner thereof; thence east five miles; thence south to the line of Highland County; thence east with said line to Paint Creek; thence in a straight line to place of beginning." All the lower portion was taken from Highland, and the upper from Ross.