Wyoming: Commentary

Wyoming Atlas of Historical County Boundaries

John H. Long, Editor; Peggy Tuck Sinko, Historical Compiler; Emily Kelley, Research Associate; Laura Rico-Beck, GIS Specialist and Digital Compiler; Peter Siczewicz, ArcIMS Interactive Map Designer; Robert Will, Cartographic Assistant

Copyright The Newberry Library 2004

Pre-Territorial Period

As territories and states were established in the American West, the Continental Divide and Rocky Mountains served as a logical barrier separating territorial jurisdictions. The area that became Wyoming was bisected by the Continental Divide, which resulted in a very complex jurisdictional history of the area prior to the establishment of Wyoming Territory. Between the time of the Louisiana Purchase in 1803 and the creation of Wyoming Territory in 1868, parts of present Wyoming fell under the jurisdiction of the District of Louisiana, Louisiana Territory, Missouri Territory, Oregon Territory, Washington Territory, Nebraska Territory, Dakota Territory, Utah Territory, Idaho Territory, Spain, Mexico, and the Republic of Texas. During those years, the District of Louisiana, the territories of Oregon, Washington, Idaho, Utah, and Dakota, as well as the Republic of Texas, established counties whose boundaries included parts of present Wyoming. All counties established by other territories and the Republic of Texas are mapped in the Atlas of Historical County Boundaries (Digital): Wyoming. While few non-Indians lived in the vast stretches of what later became Wyoming, territorial officials wanted to extend governmental authority throughout their jurisdiction to leave no place beyond the law. Some of these early counties covered thousands of square miles, yet had populations that rarely exceeded 2000 individuals.

Dakota Territory played the biggest role in the modern development of Wyoming counties. Between 1861 and 1869, major portions of present Wyoming were part of Dakota Territory. In 1867 and 1868, Dakota created four counties—Laramie, Carter (now Sweetwater), Carbon, and Albany—which became the first counties of Wyoming Territory. Although the United States Congress passed an act authorizing the creation of Wyoming Territory on 25 July 1868, delays in the appointment of territorial officers resulted in Dakota Territory continuing to exercise jurisdiction for an additional nine months. In fact, Dakota Territory created Carbon and Albany Counties in December 1868. In April and May 1869, the governor, secretary, and justices of the new territory took their oaths of office, and Wyoming Territory was officially organized on 19 May 1869.

Territorial Period

One unusual feature of Wyoming’s eastern and western state boundaries is that they are defined by meridians of longitude measured from Washington, D.C., not Greenwich, England. An act passed by the United States Congress in 1850 required the use of the Washington meridian “for all astronomical purposes” (U.S. Statutes at Large, 9:ch. 80/p. 515). The Washington meridians do not correspond neatly to Greenwich meridians, so that Wyoming’s eastern boundary, 27 degrees west of Washington, corresponds precisely to the Greenwich meridian 104 degrees, 3 minutes, 06.276 seconds. Nineteenth-century Wyoming county boundaries are sometimes defined in terms of the Washington meridian, and sometimes in terms of the Greenwich meridian. For example, the line between Carbon and Sweetwater Counties was variously defined as 107 degrees, 30 minutes (Greenwich), and 30 degrees, 30 minutes (Washington). It is clear that those two definitions were meant to be identical, and that no change in the line was intended or implied, even though the two descriptions cited above do not coincide exactly. Use of the Washington meridian was repealed by an act passed in 1912, and neither state nor county lines changed as a result. In most cases, the Greenwich meridian was used for mapping purposes in this Atlas.

One exception was made in the mapping of the 33rd meridian, which is cited in county boundary descriptions in Wyoming from 1867 to 1909. There are three possible ways to map the 33rd meridian. The first would be to follow the example above and map it to coincide with 110 degrees west longitude (Greenwich). A second approach would place it exactly 3 degrees, 06.276 seconds west of 110 degrees. The third way is to select a line halfway between 32 degrees west of Washington (the eastern boundary of Utah as defined by statute and survey), and 34 degrees west of Washington (the western boundary of Wyoming as defined by statute and survey). The third solution was the one selected. Approximately two and one-half miles separate the most eastern and western of these lines, and contemporary maps of Wyoming do not agree on the location of the 33rd meridian. Choice number three was selected because it results in a line that most nearly corresponds with the present county boundary in that part of the state.

The creation of America’s first national park, Yellowstone, in 1872, affected county boundaries. Most of the park is located in Wyoming, with small portions in Montana and Idaho. Most of the park was part of Uinta County, which, in the late nineteenth century, covered a wide strip of territory inside the western boundary of Wyoming. Questions arose regarding jurisdiction within the Park’s boundaries, and, in 1884, the Wyoming Territorial Legislature passed an act declaring that Yellowstone National Park was part of Uinta County and authorizing justices of the peace and constables for the area. The struggle between federal and local authorities continued, but Yellowstone remained technically within the jurisdiction of Uinta County until 1911.

Twentieth-Century County Boundaries

In February 1911 Wyoming county boundaries underwent major alterations. First, seven new counties were created, and, second, county boundaries were redefined to run on federal land survey lines. The redefinitions also explicitly placed Yellowstone National Park outside the boundaries of any Wyoming county. This completed a process begun a few years earlier to regularize county lines, which had previously been defined as lines of longitude or latitude or as lines running through certain landmarks. In 1880 only about one-seventh of Wyoming’s land had been surveyed, but by 1910 the land survey was about ninety percent complete (Larson, History of Wyoming, 173; Stewart, Public Land Surveys, 73). The need to reconcile the township and range system with county boundaries resulted in the wholesale adjustment of county lines in February 1911. In most cases the gain, loss, or exchange of territory was small. Eight separate legislative acts, passed between February 9 and 21, laid out this realignment. Because this legislation was so interconnected and was passed within less than a two-week period, this project maps all Wyoming counties as of 21 February, rather than on the exact date of passage, to bring together all the changes set forth in the eight separate laws.

In 1929, the counties of Park and Teton were expanded to include all of Yellowstone Park in Wyoming, once again explicitly placing it within county jurisdiction. The last county boundary change in Wyoming occurred in 1965 when approximately six square miles of United States Forest Service land was transferred from Teton County to Lincoln County. This change is not shown on many maps, including the USGS Wyoming Base Map (1:1M scale) revised in 1980, or the ESRI Digital Chart of the World. U.S. Forest Service maps do map the boundary correctly.

Sources and Acknowledgments

The three-volume Wyoming Blue Book (1974), edited by Virginia Cole Trenholm, contained helpful information on the evolution of counties and included maps. Several contemporary maps were useful in locating places. These included Masi’s Itinerary Map of Wyoming (1876?), Holt’s New Map of Wyoming (1883), and Samuel A. Mitchell’s, Territory of Wyoming (1880).

Special thanks is due Richard W. Greenwood of Greenwood Mapping, Inc., for help with the Teton County/Lincoln County boundary.