In the years that immediately preceded the establishment of what today is Grant County, this area in the heart of the Nebraska Sandhills became knows as a favorite hiding place for outlaws and other fugitives from justice due to the wide open, sparsely settled terrain and the lack of local government authority.

The cowboys that drove the first herds of Texas longhorns north along the old Abilene and Chisholm Trails realized the Sandhills region was a perfect range for cattle grazing. Rolling hills covered with hearty native grasses and numerous natural lakes made the area a cattleman's paradise. But with the cattle came rustlers and then other outlaws. Finally, in 1887, Gov. John Thayer appointed R.M. Moran to restore law and order in the territory. Sheriff Moran quickly broke up the gangs of outlaws who hid in the area and captured many notorious characters.

Grant County, named after President Ulysses S. Grant, was created by the Legislature on March 31, 1887. At the time the settlement of Whitman was designated as the county seat. But Hyannis residents felt their town was more centrally located and was better suited to serve in this role. They petitioned for an election and were successful in their bid. When a delegation traveled to Whitman to retrieve the county's records, residents of Whitman refused. The delegation finally succeeded and for years carefully guarded the documents in Hyannis while the bitter feelings continued.

The Kinkaid Act of 1904 is said to have brought an end to the days of free and open range, as new settlers hoped to establish farms on their claims. These farmers quickly became disheartened as winds blew away the tilled soil and crops failed. They sold their claims to area cattle ranchers.

According to state statistics, less than a decade ago Grant County had a larger number of cattle per square mile than any other county in the United States. The importance of the Hereford cattle breed to this county is even depicted with a mosaic picture that is mounted on the side of the courthouse in Hyannis.