Iowa Territory

The Territory of Iowa was an organized incorporated territory of the United States that existed from July 4, 1838, until December 28, 1846, when the southeastern portion of the territory was admitted to the Union as the state of Iowa. The remainder of the territory would have no organized territorial government until the Minnesota Territory was organized on March 3, 1849.

Most of the area in the territory was originally part of the Louisiana Purchase and was a part of the Missouri Territory. When Missouri became a state in 1821, this area effectively became unorganized territory. The area was closed to white settlers until the 1830s, after the Black Hawk War ended. It was attached to the Michigan Territory on June 28, 1834. At an extra session of the Sixth Legislative Assembly of Michigan held in September, 1834, the Iowa District was divided into two counties by running a line due west from the lower end of Rock Island in the Mississippi River. The territory north of this line was named Dubuque County, and all south of it was Des Moines County. When Michigan became a state in 1836 the area became the Iowa District of western Wisconsin Territory—the region west of the Mississippi River.

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