Long's Expedition 1820
The Long Expedition of 1820, officially known as the Yellowstone Expedition or the Stephen Long Expedition, was a significant U.S. government-sponsored exploration of the American West that profoundly influenced the geographical understanding and settlement patterns of Colorado and the surrounding region. Led by Major Stephen H. Long of the U.S. Army Corps of Engineers, the expedition departed from Pittsburgh in May 1820 with the primary objective of exploring the Platte River and its tributaries, examining the headwaters of the Arkansas River, and conducting scientific observations of the western territories recently acquired through the Louisiana Purchase. The expedition would result in the discovery of the peak later named Long's Peak, the establishment of important geographical records, and the production of detailed maps and journals that shaped American understanding of the Rocky Mountain frontier for decades to come. The journey marked a crucial moment in the early scientific exploration of Colorado, preceding more famous later expeditions and contributing foundational knowledge about the region's topography, Native American populations, and natural resources.
History
Major Stephen Hartman Long organized the expedition as part of the U.S. War Department's initiative to strengthen American claims to western territories and to gather scientific data about unexplored regions. The party, which included naturalists, engineers, and military personnel, initially traveled westward via the Missouri River before turning south to explore the Platte River valley. The expedition faced significant logistical challenges, including difficult terrain, limited provisions, and geographic uncertainty. In July 1820, the party reached the confluence of the South Platte and Cherry Creek, near present-day Denver, establishing one of the first documented American visits to the site that would later become Colorado's capital city. This encounter with the Front Range of the Rocky Mountains represented a pivotal moment in the expedition's journey, as the team observed and recorded detailed information about the mountain landscape, vegetation, and geological formations.[1]
The expedition continued southward along the base of the Rocky Mountains, with Long and his team climbing and surveying various peaks to determine elevation and geographical position. On June 30, 1820, the party summited what they called the "Great Peak," which rises to 14,255 feet and was eventually renamed Long's Peak in honor of the expedition leader. The ascent provided valuable data about the alpine environment and confirmed the elevation of Colorado's prominent mountains. Following this achievement, Long divided his party to explore different river systems. One group, led by Captain John Bell, descended the Arkansas River, while Long himself led another detachment down the South Platte River. The subsequent journey along the Arkansas River toward present-day Pueblo revealed additional information about Colorado's geography and natural resources, including observations of wildlife, climate patterns, and the feasibility of travel through various valleys and mountain passes.[2]
The expedition's return journey took the team eastward across the Great Plains, and Long compiled his observations into a comprehensive report published in 1823. In his official account, Long famously characterized much of the region he had traversed—particularly the vast grasslands east of the Rocky Mountains—as the "Great American Desert," a designation that would persist in geographical literature and American consciousness for several decades. This characterization, while inaccurate in its sweeping judgment about agricultural potential, reflected the expedition's limited understanding of high plains ecology and the challenges posed by water scarcity and extreme weather. Nevertheless, Long's detailed journals, maps, and scientific observations represented a significant advance in American geographical knowledge and provided the first systematic documentation of Colorado's natural features, climate, and indigenous populations.
Geography
The Long Expedition's observations and measurements contributed substantially to the accurate cartographic representation of Colorado's diverse geographic zones. The expedition traversed multiple distinct environments, from the high plains of eastern Colorado to the dramatic Front Range of the Rocky Mountains and into the intermountain valleys beyond. Long's team recorded elevations, river courses, mountain ranges, and geological formations with scientific precision that was exceptional for its time. The identification and naming of significant geographical features, particularly Long's Peak, established reference points that would guide subsequent explorers and settlers. The expedition's maps, while not perfectly accurate by modern standards, represented a major improvement over previous cartographic efforts and provided crucial information about water sources, valley locations, and mountain passes that would influence future travel routes and settlement patterns.[3]
The geographical significance of the expedition extended beyond mere mapping to include systematic observations of regional climate, vegetation zones, and ecological patterns. Long and his naturalists documented the transition from eastern grasslands to montane forests, noting the dramatic changes in flora and fauna at different elevations. Their records indicate observations of ponderosa pine forests in Colorado's mid-elevation zones, alpine tundra on the highest peaks, and distinctive riparian vegetation along river valleys. The expedition also provided detailed accounts of weather patterns, seasonal variations, and the behavior of water sources during different times of year. These observations, while not always precisely interpreted according to modern ecological understanding, established a baseline of knowledge about Colorado's natural environment that would prove valuable for later scientific study and practical planning of settlements and infrastructure development.
Notable People
Major Stephen Hartman Long served as the principal leader and organizer of the expedition, bringing his military engineering background and commitment to scientific documentation to the project. Long's reputation as a capable military officer and his previous experience with western exploration made him well-suited for the command role. Following the expedition, he continued his military career and undertook additional explorations, including the ascent of the Rocky Mountains and further surveys of western territories. Thomas Say, a naturalist and entomologist accompanying the expedition, contributed significantly to the scientific dimension of the journey through his detailed observations and collection of biological specimens. Say's work would influence the development of American natural history as a discipline, and his journal entries provided valuable information about Colorado's fauna.[4]
Captain John Bell served as Long's second-in-command and led one of the expedition's divisions during its exploratory phase. Bell demonstrated considerable skill in managing difficult terrain and coordinating with Native American groups encountered during the journey. Stephen Harriman Long and Bell's collaborative efforts, despite the division of the party, allowed the expedition to cover greater geographic territory and gather more comprehensive information than might have been possible with a unified group. The expedition also included several military personnel, enlisted men, and guides who contributed their labor and experience to the project's success. The interactions between expedition members and local Native American tribes, while limited and sometimes tense, provided early documentation of indigenous peoples and cultures in Colorado, though the accuracy and fairness of these accounts remain subjects of historical analysis.
Legacy and Impact
The Long Expedition's findings exerted considerable influence on American geographical understanding and westward expansion patterns for several decades following 1820. The expedition's reports and maps circulated among government officials, military planners, and the educated public, shaping perceptions of Colorado and the western territories. The characterization of the Great Plains as the "Great American Desert" delayed settlement and development of that region in some cases, though it also influenced the selection of Colorado's mountain valleys as more desirable locations for future colonization. The detailed information about water sources, passes, and terrain that Long's party documented provided practical guidance for subsequent travelers and settlers navigating the Colorado region.
The scientific observations and collections gathered by the expedition contributed to the broader development of American natural history and geography as academic disciplines. The species descriptions, geological observations, and climate records became reference materials for later naturalists and researchers. Long's Peak, which was named in honor of the expedition leader, became one of Colorado's most recognizable geographical landmarks and a symbol of Rocky Mountain exploration. The ascent of this peak in 1820, though not by the most technically difficult route, represented an important achievement in the early mountaineering history of North America and demonstrated the feasibility of reaching high elevation points in the Rocky Mountains.