The Territorial Legislature approved the act organizing Rock County. (Other passages date the county's full organization to February 19, 1839, and to the spring of 1839 — see those entries.)

The evidence

• “By a law approved February 13, 1839, it was enacted, " that from and after the passage of this act, the county of Rock shall be and remain to all intents and purposes, an organized county of this Territory, and shall have all the rights and privileges which organized counties in the same of right have." An election of county officers was provided for, to be held " on the first Monday of March, 1889," and the officers then chosen were empowered to borrow money on the credit of the county, not exceeding $250, for three years, at 12|^ per cent per annum, to be applied to procuring land for the seat of justice. By an act, approved February 28, 1839, the foregoing was so amended as to fix the time for election of county officers for the”

  1879-history-of-rock-county/09-rock-county-ch03-pioneer-reminiscences.md, PDF p. 353 / book p. 357

  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

• “Territory of Wisconsin limited. Feb. 13, 1839, Eock county organized. State constitutional convention, 1846, at Madison.”

  1908-brown-rock-county/00-front-matter-vol-1.md, Vol. 1, PDF p. 10

  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