On Sept. 30, 1809, the United States, on behalf of the Northwest Territory and Governor William Henry Harrison, concluded the Treaty of Fort Wayne, part of whose terms included the purchase from the Indians of a strip of land locally called "The 12 Mile Purchase" parallel to and west of "The Gore", enclosing the Whitewater Valley and comprising the largest portion of the future county. Conclusion of the treaty essentially ended Indian occupation of the county and cleared the way for settlement.