[2] The county was named for Fort Sedgwick, a military post along the Platte Trail, which was named for General John Sedgwick.

[3] Upper Crossing of the California Trail At the 2000 census there were 2,747 people in 1,165 households, including 802 families, in the county.

The racial makeup of the county was 90.50% White, 0.51% Black or African American, 0.15% Native American, 0.76% Asian, 0.07% Pacific Islander, 5.97% from other races, and 2.04% from two or more races.

[9] Of the 1,165 households 26.40% had children under the age of 18 living with them, 59.10% were married couples living together, 6.60% had a female householder with no husband present, and 31.10% were non-families.

It was the only Colorado county to vote for Charles Evans Hughes in 1916 and one of only two carried by Theodore Roosevelt in 1912, while only three Democratic presidential candidates – William Jennings Bryan in the “free silver” 1896 election plus Franklin D. Roosevelt and Lyndon Johnson in the 1932, 1936 and 1964 landslide wins – have ever carried the county, which has voted for the same candidate as the state of South Dakota in every election since its formation.