Slagle Township was formed on May 24, 1891. The first annual board meeting was held on the first Monday in April of 1892 at the home of Augustus L. Frank, due to the large number of people attending the meeting it was moved to the Union Iron Company, where the election of Township officers was held.  In 1892, Money was raised to build roads.  In 1894 the Township board voted to build a bridge across Slagle Creek and laid out the school districts and road districts.  In 1896, The Township Board voted to build a township hall for $400.00. In 1899, 5 acres were purchased to add on to the cemetery now called Sixteen Cemetery, located next to the township hall.