Morrill County is a county located in the state of Nebraska. Its county seat is Bridgeport.
In the Nebraska license plate system, Morrill County is represented by the prefix 64 (it had the sixty-fourth-largest number of vehicles registered in the county when the license plate system was established in 1922)
The Battle of Mud Springs and the Battle of Rush Creek between the U.S. army and the Cheyenne, Lakota Sioux, and Arapaho Indians took place in 1865 within what would become Morrill County.
Morrill County was formed in 1908 "carved out of Cheyenne County". It was named after Charles Henry Morrill, a president of the Lincoln Land Company.