Almost immediately after achieving territorial status, a clamor arose for statehood. On December 28, 1846, Iowa became the 29th state in the Union when President James K. Polk signed Iowa's admission bill into law. Once admitted to the Union, the state's boundary issues resolved, and most of its land purchased from the Indians, Iowa set its direction to development and organized campaigns for settlers and investors, boasting the young frontier state's rich farmlands, fine citizens, free and open society, and good government. Source: Wikipedia
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Iowa was first opened to settlement in the spring of 1833, the year following the close of the Black Hawk War and the ending of that portion of the Indian land, bordering on the Mississippi River, thirty miles in width extending from the Des Moines River south to the Turkey River north of Dubuque. At that period there were but two settlements in the "Black Hawk Purchase," one in the present limits of Dubuque County, the other in Lee County, neither of which had an organized existence. In the spring of 1834, the Iowa district (with Wisconsin) was attached to the Territory of Michigan for judicial purposes, and at the first session of the Legislature of Michigan Territory two counties were organized in the Iowa district west of the Mississippi river, Dubuque and Des Moines counties. A very few settlers came during that year, but the number increased during the succeeding years, 1835 -36, when the population reached some ten thousands.