The first two Iowa Counties were formed when Iowa was still part of Michigan Territory. In 1836 a part of Michigan Territory was formed into Wisconsin Territory. In 1838 Iowa territory was organized from the western portion of Wisconsin Territory. On December 28, 1846, Iowa entered the Union as the 29th state. On January 15, 1851, 49 counties of Iowa were created. The day is one of the most significant days in Iowa county history. read on to know more.