[2] Natrona County comprises the Casper, WY Metropolitan Statistical Area.

[3] Prior to Wyoming's settlement by European-based populations, the area's stretches played host to nomadic tribes such as Cheyenne, Arapaho, Shoshone, and Sioux.

New York investor John Jacob Astor established the settlement of Astoria on the Columbia River, and sent Robert Stuart eastward to blaze a trail and lay the foundation of a string of trading posts.

Stuart documented the South Pass Route through the Continental Divide, near the SW corner of present-day Natrona County.

Stuart's company erected the first hut in the area in 1812, near present-day Bessemer Bend.

In 1840, Father Pierre-Jean De Smet began preaching the Christian teaching to this area's indigenous peoples.

[5] Natrona County was created by the legislature of the Wyoming Territory on March 9, 1888, and it was organized in 1890.

Natrona County was named for the deposits of natron found in the area.

[7] According to George Mitchell, first mayor of Casper and member of the organization commission for Natrona County, the name was first suggested "by my old friend the late Cy Iba, who at one time owned the soda lakes.

The boundaries were adjusted slightly in 1911 and 1931, and at that point the county gained its present outline.

Bill Clinton did win a 100-vote plurality in the 1992 election due to a significant third-party vote.

The five-member board consists of commissioners, elected to staggered four-year terms.