The act of April 20 took effect. Wisconsin Territory was created from Michigan Territory, and Brown, Crawford, Iowa, and Milwaukee became counties of the new territory, together with Des Moines and Dubuque west of the Mississippi.

The evidence

• “ts of present Minnesota and North and South Dakota. (Terr. Papers U.S., 12:778-779; U.S. Stat., vol. 4, ch. 98 [1834]/p. 701) 6 September 1834 MILWAUKEE created by Michigan Territory from BROWN and IOWA; MILWAUKEE not fully organized, attached to BROWN "for judicial purposes." BROWN exchanged with CRAWFORD. (Mich. Terr. Laws, 3:1325) 7 September 1835 MILWAUKEE fully organized, detached from BROWN. (Mich. Terr. Laws, 4:136-137) 3 July 1836 The United States created Wisconsin Territory from Michigan Territory; included all of present Wisconsin, Iowa, and Minnesota; and parts of present North and South Dakota. BROWN, CRAWFORD, IOWA, and MILWAUKEE became counties in Wisconsin Territory. BROWN exchanged with Michigan Territory; CRAWFORD lost small area to Michigan Territory. DES MOINES (Iowa) and DUBUQUE (Iowa) became counties in Wisconsin Territory; DES MOINES and DUBUQUE were created by Michigan Territory on 1 October 1834. That portion of present Wisconsin and Minnesota that had been in CHIPPEWA (Mich.) and MICHILIMACKINAC (now MACKINAC, Mich.”

  https://publications.newberry.org/ahcb/documents/WI_Consolidated_Chronology.htm

  publications.newberry.org, https://publications.newberry.org/ahcb/documents/WI_Consolidated_Chronology.htm

  Grade B: Found on an institutional web page