Jefferson Territory

The Territory of Jefferson was an extralegal and unrecognized United States territory that existed from October 24, 1859 until the creation of the Colorado Territory on February 28, 1861. The Jefferson Territory included land officially part of the Kansas Territory, the Nebraska Territory, the New Mexico Territory, the Utah Territory, and the Washington Territory, but the area was remote from the governments of those five territories. The government of the Jefferson Territory, while democratically elected, was never legally recognized by the United States government, although it managed the territory with relatively free rein for 16 months. Many of the laws enacted by the Jefferson Territorial Legislature were reenacted and given official sanction by the new Colorado General Assembly in 1861.

On August 25, 1855, the Kansas Territory created Arapahoe County, a huge county that included the entire western portion Kansas to the Rocky Mountains. The boundaries of Arapahoe County were defined as: beginning at the northeast corner of New Mexico, running thence north to the south line of Nebraska and north line of Kansas; thence along said line to the east line of Utah Territory; thence along said line between Utah and Kansas territories, to where said line strikes New Mexico; thence along the line between said New Mexico and the territory of Kansas to the place of beginning.

Occupied primarily by Cheyenne and Arapaho Indians with few white settlers, the county was never organized. The leaders of the Kansas Territory were preoccupied with the violent events of Bleeding Kansas, so little time or attention was available to attend to the needs of the far western portion of the territory. The question of whether to admit Kansas to the union as a slave state or free state dominated discussion in the populous eastern portion of the territory and led to three failed constitutional proposals between 1855 and 1858 (the Topeka, Lecompton and Leavenworth constitutions). The United States Congress was likewise preoccupied with threats of secession by the slave states.

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