[3] The county is named after Horace Greeley,[4] editor of the New York Tribune, who encouraged western settlement with the motto "Go West, young man".

Tribune was named the temporary county seat, defeating Horace in an election held that November.

By 1910, the population had significantly increased, leading to the establishment of 13 school districts and a scattering of post offices including at Tribune, Horace, Hurt, Sidney, Thelma, and Youngville.

[6] According to the United States Census Bureau, the county has a total area of 778 square miles (2,020 km2), all of which is land.

[7] It is the largest of five United States counties and twelve (Virginia) independent cities that officially have no water area.

As of January 1, 2009, Greeley County and the City of Tribune have operated as a unified government.

The last time a Democratic candidate won the county was in 1976, and a Democratic candidate has only won the county three times in its history: 1932 (Franklin D. Roosevelt), 1964 (Lyndon B. Johnson), and most recently in 1976 by Jimmy Carter.

The Kansas Constitution was amended in 1986 to allow the sale of alcoholic liquor by the individual drink with the approval of voters.

Greeley County appears in several episodes of the television series Prison Break.