Sherman Township is one of sixteen townships in Calhoun County, Iowa, USA. As of the 2000 census, its population was 461.HistorySherman Township was created circa 1868.GeographySherman Township covers an area of 35.58sqmi and contains no incorporated settlements. However, part of the Twin Lakes census-designated place is in the southern part of the township, surrounding North Twin Lake. According to the USGS, it contains three cemeteries: Leith, Memorial Park and Swedish.