Thomas Jefferson, a delegate to the Continental Congress from Virginia, a statesman and lawyer, a Minister to France, the first US Secretary of State, and the country’s third president, imagined the United States as a republic sustained by independent, landowning farmers whose virtue, in his view, derived from close, direct engagement with the land. Land ownership was central to his understanding of equal citizenship; liberty depended on access to land, and the West was the place where future generations would manifest and secure that independence.​ To preserve this agrarian republic, Jefferson argued that the nation needed “room enough” for its descendants and looked westward toward what he described as an “empire of liberty,” populated by these smallholders and tied together by commerce and shared political institutions.​ Jefferson held Idaho in his mind, though he never laid eyes on the sometimes shocking and always inspiring landscapes that would become the Gem State. But his directive to Lewis and Clark and the Corps of Discovery became one of America’s earliest episodes in a longer story in which knowledge gathering, diplomacy, and mapping served the future appropriation and settlement of western lands.​ 

In the 1770s, Jefferson was helping articulate a Revolutionary political philosophy that asserted the colonies’ right to self-government, free trade, and control over their own territorial development, laying the intellectual groundwork for future western expansion. As the son of a surveyor, he had long been attuned to maps, rivers, and boundaries; by the mid-1770s, he had begun to imagine the United States as an “empire for liberty,” a continental republic of smallholders and trading communities spreading across vast interior homelands already occupied by Indigenous nations.​ 

Decades later, as president, Jefferson translated this conceptual project into policy. The 1803 Louisiana Purchase provided a diplomatic opening to sponsor an overland expedition to gather scientific data, explore potential commercial routes, and initiate formal diplomatic relationships with Native nations in the trans-Mississippi West.​ In his instructions to Meriwether Lewis, Jefferson’s Revolutionary-era commitments to knowledge, commerce, and negotiated relationships with Indigenous communities coalesced into a directive that placed scientific observation and Native diplomacy at the heart of the Corps of Discovery’s work.​ 

Yet the tension between a political philosophy that celebrated independence and a continental project that depended on Indigenous dispossession is central to understanding the earliest phases of development in the American West, as viewed alongside a reading of Early-Republic-era history.​ 

Sacajawea was likely born in the late 1780s in the Lemhi River Valley of present-day Idaho, as a member of the Agaidika (Salmon Eaters) band of the Shoshone, whose seasonal rounds and trade networks tied the Northern Rockies to a wider Indigenous world.​ Around age twelve, Hidatsa raiders captured her near Three Forks, Montana, and took her to their villages along the Knife River in what is now North Dakota, where she entered a new cultural and linguistic landscape as a captive. Several years later, French-Canadian trader Toussaint Charbonneau took her as his wife.​ When Meriwether Lewis and William Clark established winter quarters at Fort Mandan in 1804, Sacajawea was pregnant with her son, Jean Baptiste, and living in this diverse upper Missouri River community where Hidatsa, Mandan, and French-Canadian families intersected with the newly arrived Corps of Discovery.​ The expedition journals offer only fragmentary references to her early life, so much of her biography before 1805 has been reconstructed from scattered journal entries, fur-trade records, and Shoshone oral traditions, reminding historians that she appears in the written record most clearly at the moment when her life intersects with a federal exploratory project.​ 

Sacajawea’s participation in the expedition must be understood within this larger Jeffersonian framework. At Fort Mandan, Lewis and Clark hired Charbonneau as an interpreter, and with him came Sacajawea, who traveled west with the Corps while caring for Jean Baptiste and working within a multilingual, multi-tribal expedition team.​ Contrary to the popular portrayal of Sacajawea as the singular “guide” who led the party to the Pacific, the journals indicate that her geographical knowledge was most consequential in and around her Shoshone homelands, while the day-to-day work of wayfinding depended on a broad network of Indigenous guides and advisors encountered along the route. Her contributions were nonetheless significant. She gathered edible plants, assisted with camp labor, interpreted during key diplomatic exchanges, and famously helped salvage important equipment and documents after a pirogue capsized on the Missouri River. Perhaps most importantly, her and her infant son’s presence communicated the Corps’ non-military posture to many Native communities. As William Clark noted, the sight of a young woman with a child traveling with strangers served as a powerful visual signal that this was not a war party.​ 

Sacajawea’s elevation from expedition member to national icon gained momentum during the Corps’ centennial celebration. Suffrage-era activists and later women’s history advocates adopted her as a symbol of courage, endurance, and women’s contributions to nation-building, often framing her story as evidence that women had always been present in foundational American narratives.​ Monuments, including the 1905 statue in Portland, Oregon, and subsequent artistic representations across the West, usually presented her as a forward-looking figure, sometimes with a child in arms, embodying both the burdens and possibilities of westward movement.​ 

For Idaho, Sacajawea is a regional historical figure whose life is rooted in specific places and a national symbol whose meaning has been continuously renegotiated in courts of public memory. And now, as we celebrate 2026 and America250, a national moment to reflect on the ideals of independence, liberty, and justice, her story invites Idahoans to consider how Jefferson’s Revolutionary-era ideas about these enduring American values have, at times, manifested in the conquest of indigenous lands, labor, and knowledge. ​