1852
A settler came to Wisconsin in 1852, locating in the town of Rock.
Rock CountyGrade A · 1 independent source
The evidence
“P. 0. Janesville ; born in Scotland Aug. 21, 1837 ; came to Wisconsin in 1852, locating in the town of Rock, where he worked on his father's farm for a number of years ; about the year 1867, he moved to La Prairie, and purchased a farm of 340 acres in Sees. 29 and 30, his present homestead. Married, June 3, 1859, Miss Mary E.”
1879-history-of-rock-county/26-bios-la-prairie.md, PDF p. 832
Butterfield, C. W., et al. The History of Rock County, Wisconsin: its early settlement, growth, development, resources, etc. Chicago: Western Historical Company, 1879. Cornell University Library via the Internet Archive, archive.org/details/cu31924028871585.
Grade A: Found on a page of one of our sources