From Czechs in Nebraska, Sioux County Section, published 1926:
The northwestern corner of our state was originally known as Sioux County and later was divided into three counties of almost equal size: Sioux, Dawes and Sheridan. This occurred in 1886, when the inhabitants of the south portion of Dawes County asked for the division because Chadron, the county seat, was distant and there were no bridges across the Niobrara River, while the timbered hills were difficult to traverse. All the records on hand as to Czech settlers in this county are the following, who lived there in the early nineties:
P. O. Canton:
John Pokorny, born in Ostasov, Hrotovice; Frank Koudelka. Hodslavice, Novy Jicin; Joseph Bame Sr., Dolni Lukavice, Prestice; Joseph Moravek, Sloupnice, Chrudim.
P. O. Harrison:
Anton Moravek, Rychnov, Kralove Hradec; Joseph Stastny, Vranov. Tabor.
Later, after 1904, when the Kincaid law went into effect, allowing an individual to take up 640 acres as a homestead, more Czechs settled there, but evidently did not stay, for at present there are only five families of this nationality in this county.Business and Persons Gazetteer.
This link has information about people in the early days of Sioux County, and a listing of many people that lived in Sioux County from 1890-1891.
Sioux County Newspapers
Search the Sioux County Newspaper Digital Archive, covering 6 newspapers from 1860-the 2020s.
The current newspaper for Sioux County is the Crawford Clipper-Harrison Sun.