Mitchell was created on January 15, 1851 (Organized in 1854) from Unorganized Territory. The County was named for either John Mitchel, an Irish patriot, or John Mitchell, an early surveyor. The County Seat is Osage.

Counties adjacent to Mitchell County are Mower County, Minnesota (north), Howard County (east), Floyd County (south), Cerro Gordo County (southwest), Worth County (west). Cities and Towns Include Carpenter, McIntire, Mitchell, Orchard, Osage, St. Ansgar, Stacyville.

Mitchell County was originally part of Fayette County until it was established in 1851 at a winter session of the Iowa legislature. The county was named either after John Mitchell, an Irish patriot and refugee of 1848, or after an early surveyor.

The first settlers of the county were Leonard Cutler and his son. They passed through Mitchell County in the fall of 1851 and returned the following spring to make a land claim. The first families to settle were the families of L. S. Hart and Orrin, his son, who came in the summer of 1852.

The county originated in 1854 and county officers were first elected August 7, 1854. Each newly-elected officer opened his county office in his own cabin until a building could be provided.

Perhaps the most interesting history of the county involves the battle of the county seats. The first county seat was located in Mitchell because it was centrally located in the county, a very important asset at this time. The people of Osage objected to Mitchell and called for an election. In this election Osage won, but the people of Mitchell contested the election. It was rumored that votes for Osage were bought and paid for with merchandise. The two towns now resorted to every trick known to politicians to gain the county seat.

In 1858 Osage agreed to build a courthouse and jail, and give them to the county. At the same time Mitchell built a courthouse and agreed to give it to the county, but it never did.

Later Osage and Charles City joined forces, since Charles City also wanted to be a county seat, of Floyd County. To better locate both cities centrally in their respective counties, Floyd County gave Mitchell County a three-mile strip of territory on the north end of Floyd County.

This controversy was taken to the courts and arguments were thrown back and forth between the two towns. Finally the matter was called up to trial in a adjoining county. The people of Mitchell were not given notice of this and thus failed to appear for the trial. The judge ruled in favor of the town of Osage. Then, in the middle of the night the county records were moved to Osage, before a contest could be filed. They have been there ever since.

The courthouse that Osage built in 1858 is still in use today. Except for a $100,000 addition in 1976, the red brick building is unchanged and has become one of the oldest courthouses in the state.

Originally, the Mitchell County Board of Supervisors was a body of 17; one from each township. In 1875, the Board was reduced to five members. In 1926, the county was redistricted, and the number of Board numbers changed to three. The first Lieutenant Governor of Iowa, Oran Faville, came from Mitchell County.

Biedermann, William H., Brief History of Mitchell County, 1973
Zola Naig, Mitchell County Recorder