Arrappahoe County, Jefferson Territory

Arrappahoe County was a county of the extralegal United States Territory of Jefferson that existed from November 28, 1859, until February 28, 1861. The county name was also spelled Arapaho County, Arapahoe County, Arrapahoe County, and Arappahoe County. The county seat was Denver City.

In July 1858, gold was discovered along the South Platte River in Arapahoe County, Kansas Territory. This discovery precipitated the Pike's Peak Gold Rush. Many residents of the mining region felt disconnected from the remote territorial governments of Kansas and Nebraska, so they voted to form their own Territory of Jefferson on October 24, 1859. On November 28, the General Assembly of the Territory of Jefferson organized 12 counties: Arrappahoe County, Cheyenne County, El Paso County, Fountain County, Heele County, Jackson County, Jefferson County, Mountain County, North County, Park County, Saratoga County, and St. Vrain's County. The legislation that created Arrappahoe County declared:

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