Wisconsin Territory Wisconsin Territory became an organized territory of the United States by an act of U.S. Congress passed on April 20, 1836 which went into effect on July 3, 1836. The Territory became the state of Wisconsin, the 30th U.S. state on May 29, 1848. Belmont, Wisconsin was initially chosen as the capital of the territory, but this was changed in October 1836 to the current capital of Madison.
