|Territory of Wisconsin|
|Organized incorporated territory of the United States|
Map of the Wisconsin Territory, 1836–1848
Belmont (July–December 1836)
|• Type||Organized incorporated territory|
|James Duane Doty|
|Nathaniel P. Tallmadge|
|John Catlin (acting)|
|Legislature||Legislative Assembly of the Territory of Wisconsin|
• Organic Act effective
|July 3 1836|
• Iowa Territory split off
|July 4, 1838|
|May 29 1848|
The Territory of Wisconsin was an organized incorporated territory of the United States that existed from July 3, 1836, until May 29, 1848, when an eastern portion of the territory was admitted to the Union as the State of Wisconsin. Belmont was initially chosen as the capital of the territory. In 1837, the territorial legislature met in Burlington, just north of the Skunk River on the Mississippi, which became part of the Iowa Territory in 1838.  In that year, 1838, the territorial capital of Wisconsin was moved to Madison.
The Wisconsin Territory initially included all of the present-day states of Wisconsin, Minnesota, and Iowa, and part of the Dakotas east of the Missouri River. Much of the Territory had originally been part of the Northwest Territory, which was ceded by Britain in 1783. The portion in what is now Iowa and the Dakotas was originally part of the Louisiana Purchase and was split off from the Missouri Territory in 1821 and attached to the Michigan Territory in 1834.
The portion that was formerly part of the Northwest Territory and which later became the state of Wisconsin was part of the Indiana Territory when this was formed in 1800. In 1809, it became part of the Illinois Territory; then, when Illinois was about to become a state in 1818, this area was joined to the Michigan Territory. Then, the Wisconsin Territory was split off from Michigan Territory in 1836 as the state of Michigan prepared for statehood.  In 1838, the section of the territory to the west of the Mississippi became the Iowa Territory.
Most of the remaining land of the original Wisconsin Territory was originally part of the Louisiana Purchase, though a small fraction was part of a parcel ceded by Great Britain in 1818. This land west of the Mississippi had been split off from the Missouri Territory in 1821 and attached to the Michigan Territory in 1834. In 1838, the Iowa Territory was formed, reducing the Wisconsin Territory to the boundaries for the next ten years; upon granting statehood to Wisconsin, its boundaries were once again reduced, to their present location. 
There are irregularities in the historical timeline at the outset of the Territory. After Congress refused Michigan's petition for statehood, despite meeting the requirements specified in the Northwest Ordinance, the people of Michigan authorized its constitution in October 1835 and began self-governance at that time. Yet, Michigan did not enter the Union until January 26, 1837, and Congress did not organize the Wisconsin Territory separately from Michigan until July 3, 1836.
Hoping to provide for some continuity in governance during that interim, acting Governor of the Michigan Territory, Stevens T. Mason, issued a proclamation on August 25, 1835, that called for the election of a western legislative council (the Seventh Michigan Territorial Council), which became known as the Rump Council. This council was to meet in Green Bay, Wisconsin, on January 1, 1836. However, because of the controversy between Michigan and Ohio over the Toledo Strip, known as the Toledo War, President Jackson removed Mason from office on August 15, 1835, and replaced him with John S. Horner. Horner issued his own proclamation on November 9, 1835, calling for the council to meet on December 1, 1835 — giving delegates less than a month to learn of the change and travel to the meeting. This caused considerable annoyance among the delegates, who ignored it. Even Horner himself neglected to attend. The Council convened on January 1 as previously scheduled, but Horner, while reportedly intending to attend, was delayed by illness and in the Governor's absence the council could do little more than perform some administrative and ceremonial duties. For its concession to the Toledo Strip, Michigan was given the Upper Peninsula. 
President Andrew Jackson appointed Henry Dodge Governor and Horner Secretary. The first legislative assembly of the new territory was convened by Governor Dodge at Belmont, in the present Lafayette County, on October 25, 1836.  In 1837, Burlington, Iowa, became the second territorial capital of the Wisconsin Territory. The next year, the Iowa Territory was created and the capital was moved to Madison. 
When Wisconsin became a state on May 29, 1848, no provision was made for the section of land between the St. Croix River and the Mississippi River which had previously been organized as part of Wisconsin Territory. Additionally when Iowa became a state on December 28, 1846, no provision was made for official organization of the remainder of what had been Iowa Territory.  In the Congress of 1846–47, when Wisconsin was being organized as a state, the Wisconsin territorial delegate to Congress Morgan L. Martin pushed through a bill to organize a territory of Minnesota to encompass this land. While the bill passed in the House, it did not pass the Senate. In the following session a bill by Stephen A. Douglas was introduced in the Senate but also did not pass. In the summer of 1848, residents in the area organized themselves and called a series of meetings. As these meetings commenced, the most recent territorial delegate to congress John H. Tweedy officially tendered his resignation, thus vacating the seat. Secretary of State John Catlin went to Stillwater, Minnesota, and in the capacity of acting governor of the territory issued writs for a special election to fill the seat, which was won by Henry H. Sibley on October 30.  
When Sibley went to Washington to take his seat in Congress, he was not immediately recognized. Only after a long political battle was he allowed to take his seat on January 15, 1849. For a period of time, there were simultaneously representatives in Congress from both the State of Wisconsin and the Territory of Wisconsin, an unprecedented situation. Sibley made it his first order of business to push through the statute necessary to establish the Territory of Minnesota, which occurred on March 3, 1849.  
- John S. Horner 1836–37
- William B. Slaughter 1837–41
- Francis J. Dunn 1841
- Alexander P. Field 1841–43
- George Rogers Clark Floyd 1843–46
- John Catlin 1846–48
The Legislative Assembly of the Wisconsin Territory consisted of a Council (equivalent to a senate) and Representatives. The first session of the First Legislative Assembly convened at Belmont, Iowa County (now in Lafayette County), on October 25, and adjourned December 9, 1836. The Council at that time had 14 seats, and was presided over by Henry Baird of Brown County. There were 26 Representatives; the Speaker of the House was Peter H. Engle of Dubuque County ("Dubuque County" at this time embraced all of the territory west of the Mississippi River and north of the latitude of the south end of Rock Island).
The last session of the Assembly was the Second Session of the Fifth Legislative Assembly, which convened February 7, and adjourned March 13, 1848. The President of the 13-member Council was Horatio N. Wells of Milwaukee, and the Speaker of the 26-member House of Representatives was Timothy Burns of Iowa County. 
- Henry S. Baird 1836–39
- Horatio N. Wells 1839–41
- Mortimer M. Jackson 1841–1845
- William Pitt Lynde 1845
- A. Hyatt Smith 1845–48
- George Wallace Jones 1836–1838 24th Congress, 25th Congress
- James Duane Doty 1839–41 25th Congress, 26th Congress
- Henry Dodge 1841–45 27th Congress, 28th Congress
- Morgan Lewis Martin 1845–47 29th Congress
- John Hubbard Tweedy 1847–48 30th Congress
- Henry Hastings Sibley 1848–49 30th Congress
- Burlington Hawkeye
- James Clarke (Iowa)
- Governors of the Territory of Wisconsin
- Historic regions of the United States
- History of Wisconsin
- Territorial evolution of the United States
- Strong, Moses McCure (1885). History of the territory of Wisconsin, from 1836 to 1848. Madison: Democrat Printing Company. Retrieved October 12, 2014.
- State of Wisconsin (1921). Wisconsin statutes. Democrat Printing Co. p. 2701. Retrieved April 18, 2015.
- Strong, Moses McCure. History of the Territory of Wisconsin, from 1836 to 1848 Madison: Democrat Printing Oo., State Printers, 1885; pp. 67-266
- Schafer, Joseph (1920). "The Rump Council". Wisconsin Historical Society Proceedings, 1920. Madison: Wisconsin Historical Society.
- History of Wisconsin – Chapter 2 – Wisconsin as a Territory
- Mahan, Bruce E.; Gallaher, Ruth A. (1931). Stories of Iowa for Boys and Girls. New York: Macmillan.
- "Chapter 2 — Founding Documents" (PDF). 2013 – 2014 Minnesota Legislative Manual (Blue Book) (PDF). Saint Paul, MN: Office of the Minnesota Secretary of State. 2013. p. 50. Retrieved August 19, 2014.
- Shortridge, Wilson P. (August 1919). "Henry Hastings Sibley and the Minnesota Frontier". Minnesota History Bulletin. 3 (3): 115–125. Retrieved August 19, 2014.
- The History of Racine and Kenosha Counties, Wisconsin. Chicago: Western Historical Company. 1879. pp. 55–56. Retrieved August 25, 2014.
- Sibley, Henry H. (1880).
"Reminiscences of the Early Days of Minnesota". Retrieved August 18, 2014. Cite journal requires
- Williams, John Fletcher (1894). "Henry Hastings Sibley: A Memoir". Collections of the Minnesota Historical Society. Minnesota Historical Society. 6: 257–310. Retrieved August 19, 2014.
- Heg, J. E., ed. (1882). The Blue Book of the State of Wisconsin 1882. Madison: Wisconsin Secretary of State. pp. 161, 174.
- Wisconsin State Historical Society, Turning Points, Wisconsin Territory
- John S. Horner Biography
- The Rump Council
- An Act establishing the Territorial Government of Wisconsin
- Toledo War information regarding Upper Peninsula of Michigan