The first permanent settlers in Sheridan Township were Mr. and Mrs. Jacob Harman, in March 1855. They lived first at Hickory Grove until building their new home. He raised corn and wheat. In 1856 he plowed a furrow from his home in Sheridan Township to Grinnell to guide other settlers.
The first marriage in Sheridan Township was that of Susan Harman and John Reberg. Uriah Jones officiated the ceremony. The first birth was of twin daughters, Lucy and Frances in 1859, to Mr. and Mrs. Jonas Harman. The first death was of Mrs. Hervey Coulsen, October 20, 1855. She was initially buried near Walnut Creek, then moved to the Kent Cemetery.
The first schoolhouse was built in Sheridan in 1858, on the south side of Hickory Grove. In a few years there were three school districts, then nine as was the usual pattern in Poweshiek County.
Sheridan Township was organized September 5, 1866, after first being a part of Bear Creek, Sugar Creek, Jefferson, Madison, Washington, Grinnell, and Chester Townships at different times. The first trustees were M.M. Snider, P.J. Stowells and Jacob Harman. A levy of 2 mils on the dollar was set for road purposes.
Early ministers preached at the school buildings. Rev. I.N. Busby was a Methodist minister assigned to northern Poweshiek County, preaching in schools in Sheridan, Ottawa, and Pleasant Prairie before the Methodist Church building was erected in 1877. The Evangelical Lutheran Trinity Church was built just across the township line in Malcom Township, and was served by a minister who also served a congregation just to the north of Sheridan Township. Many of the members of these congregations lived in Sheridan Twp.
The first cemetery was platted in Section 4. Some of the bodies were moved to where the church and its nearby cemetery were located when the church was built in Sheridan, and some to Grandview Cemetery in nearby Tama County. The Sheridan Post Office was established in 1877. The first general store was opened in 1887 by Steven Webster.
A real estate hoax was foisted on the public, based on a town called Ottawa City in the northeastern part of Section 12. The town was platted and many parcels sold, mostly to prospective settlers in the eastern United States, but no town was ever built.
(from Poweshiek County Iowa Historical and Genealogial Society)