Editing Adams County, Colorado (section)

==History==<!-- This section is linked from [[Arapahoe County, Colorado|Arapahoe County]], Colorado -->
On May 30, 1854, the [[Kansas–Nebraska Act]] created the [[Territory of Nebraska]] and [[Territory of Kansas]], divided by the [[40th parallel north|Parallel 40° North]] ([[Baseline Road (Colorado)|168th Avenue]] in present-day Adams County). The future Adams County, Colorado, occupied a strip of northern [[Arapahoe County, Kansas Territory]], immediately south of the [[Nebraska Territory]].

In 1859, [[John D. Henderson|John D. "Colonel Jack" Henderson]] built a ranch, trading post, and hotel on Henderson Island in the [[South Platte River]] in [[Arapahoe County, Kansas Territory]]. Jack Henderson was the former editor and proprietor of the [[Leavenworth, Kansas|Leavenworth]] ([[Kansas Territory]]) Journal and an outspoken pro-slavery politician who had been accused of vote fraud in eastern Kansas. Henderson sold meat and provisions to gold seekers on their way up the South Platte River Trail to the gold fields during the [[Pike's Peak Gold Rush]]. Henderson Island was the first permanent settlement in the South Platte River Valley between [[Fort Saint Vrain]] in the [[Nebraska Territory]] and the [[Denver, Colorado#History|Cherry Creek Diggings]] in the [[Kansas Territory]]. Jack Henderson eventually returned to eastern Kansas and fought for the [[Union (American Civil War)|Union]] in the [[American Civil War]]. Henderson Island is today the site of the Adams County Regional Park and Fairgrounds.

The eastern portion of the [[Kansas Territory]] was [[list of U.S. states by date of statehood|admitted to the Union]] as the [[Kansas#History|State of Kansas]] on January 29, 1861, and on February 28, 1861, the remaining western portion of the territory was made part of the new [[Colorado Territory]].<ref name= StateGovHistCO>{{cite web|date=April 18, 2001|url=http://www.colorado.gov/dpa/doit/archives/arcgov.html|title=State Government History|publisher=State of Colorado, Department of Personnel & Administration, Colorado State Archives|access-date=November 28, 2006|archive-url=https://web.archive.org/web/20061130002528/http://www.colorado.gov/dpa/doit/archives/arcgov.html|archive-date=November 30, 2006|url-status= live}}</ref> The [[Colorado Territory]] created [[Arapahoe County, Colorado#History|Arapahoe County]], on November 1, 1861, and Colorado was [[list of U.S. states by date of statehood|admitted to the Union]] on August 1, 1876.<ref name= StateGovHistCO />

In 1901, the [[Colorado General Assembly]] voted to split [[Arapahoe County, Colorado#History|Arapahoe County]] into three parts: a new Adams County, a new [[consolidated city-county|consolidated]] [[Denver, Colorado#History|City and County of Denver]], and the remainder of the Arapahoe County to be renamed [[South Arapahoe County, Colorado|South Arapahoe County]]. A ruling by the [[Colorado Supreme Court]], subsequent legislation, and a [[referendum]] delayed the creation of Adams County until November 15, 1902. [[Governor of Colorado|Governor]] [[James Bradley Orman]] designated [[Brighton, Colorado|Brighton]] as the temporary Adams [[county seat|County Seat]]. Adams County originally stretched {{convert|160|mi|km|abbr=off|sp=us}} from present-day Sheridan Boulevard to the [[Kansas]] state border. On May 12, 1903, the eastern {{convert|88|mi|km|abbr=off|sp=us}} of Adams County was transferred to the new [[Washington County, Colorado|Washington County]] and the new [[Yuma County, Colorado|Yuma County]], reducing the length of Adams County to the present {{convert|72|mi|km|abbr=off|sp=us}}. On November 8, 1904, Adams County voters chose [[Brighton, Colorado|Brighton]] as the permanent [[county seat]].

A 1989 vote transferred {{convert|53|mi2|km2|abbr=off|sp=us}} of Adams County to the [[Denver, Colorado|City and County of Denver]] for the proposed [[Denver International Airport]], leaving the densely populated western portion of the county as two oddly-shaped peninsulas. Adams County lost the tip of its northwest corner when the consolidated [[Broomfield, Colorado|City and County of Broomfield]] was created on November 15, 2001.