Fall 1842
A house of worship was constructed on the northeast quarter of section 35, town of Milton, and the congregation became known as the First Congregational Church of Rock County.
Rock CountyGrade A · 1 independent source
The evidence
“Adams as moderator the above church was organized with nine members. Up to 1842 services were held in private houses, and it was called the Congregational Church of Du Lac; but in the fall of that year a house of worship was constructed on the northeast quarter of section 35, town of Milton, and it became known as the First Congregational church of Rock county. The first minister was Rev.”
1908-brown-rock-county/31-smaller-cities-villages-towns.md, Vol. 2, PDF p. 167 / book p. 674
Brown, William Fiske, editor. Rock County, Wisconsin: A New History of Its Cities, Villages, Towns, Citizens and Varied Interests, from the Earliest Times, Up to Date. Chicago: C. F. Cooper & Co., 1908. 2 vols. archive.org/details/rockcountywiscon01brow, archive.org/details/rockcountywiscon02brow.
Grade A: Found on a page of one of our sources