[2] In the Nebraska license plate system, Hooker County is represented by the prefix 93, because it had the smallest number of registered vehicles out of the state's 93 counties when the licensing system was established in 1922.

[3] Hooker County was formed in 1889 with construction of a line for Chicago, Burlington and Quincy Railroad into the territory.

[5] The terrain of Hooker County consists of low rolling hills running east–west.

The Middle Loup River flows eastward through the upper part of the county.

Hooker County voters have been overwhelmingly Republican ever since World War II.

The last Democratic presidential candidate to carry the county was Franklin D. Roosevelt in 1932 when the region was decimated by the Dust Bowl, and in no presidential election since 1936 has the Democratic nominee reached thirty percent of the county's vote – a record of Republican dominance equalled only by the Unionist Kentucky counties of Jackson and Clinton where no Democrat has passed thirty percent since before 1896.