The Washington, Simpson, Kern Expedition of 1849: Reconnaissance, Ancient Ruins, and a Lost Opportunity for Peace

In the late summer of 1849, a U.S. Army column marched out of Santa Fe and into Navajo country on a mission that would reshape the political and cultural landscape of the Southwest. Officially titled the Military Reconnaissance from Santa Fe, New Mexico to the Navajo Country, this journey—now remembered as the Washington, Simpson, Kern Expedition—was equal parts scientific survey, military reconnaissance, and cultural collision. It ended with the death of Chief Narbona, one of the most respected Navajo leaders of the era, and it set in motion decades of mistrust that would define U.S.–Navajo relations (perhaps even into today).

A Mission Built on Transition and Tension

The expedition emerged from a moment of profound upheaval. The Mexican-American War had just concluded, and the Treaty of Guadalupe Hidalgo had transferred vast territories to U.S. control. New Mexico, now under American governance, was a volatile frontier where longstanding patterns of raiding, livestock theft, and intercommunity conflict collided with the ambitions of a new colonial power.

The Army’s objectives reflected that tension. Washington’s command was tasked with enforcing treaty obligations—specifically the return of Mexican captives and stolen property—while simultaneously conducting a geographical and scientific survey of a region that, to U.S. officials, remained largely unmapped. The military goals came first. Peace, if it happened at all, would be defined on American terms.

The Personalities Driving the Expedition

Brevet Lieutenant Colonel John M. Washington, both military commander and Governor of New Mexico, led the force. Alongside him was First Lieutenant James H. Simpson of the Corps of Topographical Engineers, whose job was to document the terrain “as the movements of the troops will permit.” Simpson’s journal would become the expedition’s most enduring artifact—a meticulous blend of geology, ethnography, and military observation.

Supporting Simpson were Richard and Edward Kern, whose artistic and topographical work captured the landscapes, ruins, and communities encountered along the way. Their sketches remain some of the most evocative visual records of the Southwest in the mid-1800’s.

The expedition eventually grew to roughly four hundred men: Regular Army troops, Mexican Volunteer Infantry, Mounted Militia, and Pueblo auxiliaries whose local knowledge proved essential as the terrain grew harsher.

Into the High Desert

The logistical challenges were immense. Wagons were abandoned for pack mules at Jémez Pueblo as the command pushed westward across the Jemez Mountains, over the Rio Puerco, and toward the legendary Navajo stronghold of Canyon de Chelly.

Simpson’s journal is filled with geological detail—coal seams, gypsum deposits, volcanic formations, mesa heights, petrified wood. These weren’t idle observations. They were strategic assessments, proof that the land was navigable by U.S. forces, even with artillery. The Army was learning the terrain in order to control it.

Encountering the Ancient Southwest

One of the expedition’s most significant contributions was its documentation of the ancient Pueblo ruins of Chaco Canyon. Simpson recorded sites such as Pueblo Pintado, Hungo Pavie, Chettro Kettle, and Pueblo Bonito, marveling at their masonry and architectural sophistication. He described them as a “combination of science and art,” far surpassing the buildings of contemporary New Mexicans. His speculation about Aztec or Toltec origins reflects the era’s fascination with lost civilizations and the persistent misunderstanding of Indigenous histories.

Canyon de Chelly and the Death of Narbona

The emotional and political climax of the march came at Canyon de Chelly. Long rumored to be an impregnable Navajo fortress, the canyon proved less defensible than expected, but its towering sandstone walls left a deep impression on the Americans.

It was here that a dispute over a stolen horse spiraled into violence. Chief Narbona—elder statesman, diplomat, and advocate for peace—was shot and killed. His death was catastrophic for Navajo diplomacy. With him died the best chance for a negotiated peace grounded in mutual respect. The loss hardened Navajo resistance and shaped the leadership of his son, Manuelito, who would become one of the most formidable opponents of U.S. expansion.

A Treaty Signed Under the Shadow of Violence

Despite the bloodshed, Washington convened a council with Navajo leaders, including Mariano Martinez. A treaty was signed, demanding the return of captives and livestock and affirming Navajo submission to U.S. authority. But the circumstances were unmistakable: this was not a meeting of equals. The treaty was negotiated deep within Navajo territory, under the watchful eyes of armed troops and artillery.

The Return: Zuñi, El Morro, and the Layers of History

On the return journey, the expedition passed through Zuñi Pueblo, where Simpson recorded the distinctive terrace architecture and the community’s origin story “from the setting sun.” At El Morro—Inscription Rock—Simpson and Richard Kern copied Spanish inscriptions dating back to the 1500s, adding yet another layer to a sandstone palimpsest of conquest and encounter.

Simpson ended his journal with a stark assessment of the land: “almost universal barrenness,” punctuated by small fertile valleys. Yet he recognized the strategic value of the journey. The expedition had demonstrated that the region was traversable by U.S. forces. It was a logistical proof of Manifest Destiny.

Legacy and Fallout

The Washington, Simpson, Kern Expedition is more than a military report. It captures a transitional moment in the American West—a convergence of scientific curiosity, cultural encounter, and imperial ambition. It documents landscapes on the brink of transformation and communities navigating the pressures of a rapidly expanding colonial state.

For the Navajo, the death of Narbona became a defining memory, a catalyst for resistance, and a symbol of broken promises. For the United States, the expedition mapped not only terrain but also the political fault lines that would erupt in the decades to come.

The journey revealed the land’s contours. It also revealed the limits of American diplomacy—and the cost of ignoring Indigenous sovereignty.

This post is meant to serve as an entry point for future posts detailing an experiment using GeoAI techniques with Lieutenant Simpson's original map, as produced is 1849, to attempt to "discover" military encampments related to this expedition. This work has been attempted in the past, but never with GeoAI techniques.

Please read Frank McNitt's, Navaho Expedition, published by the University of Oklahoma. Dr. McNitt is the authority on this expedition, and much of what is summarized above is founded on his work together with Lieutenant Simpson's original report to Congress which was subsequently published in 1852. The map is a georeferenced map of the original Simpson map placed on top of a current satellite map, as produced by Richard Ott, archaeologist and founder and owner of GeoHeritage, LLC, a GeoAI Heritage company.

Tom Christian, PhD (c)