In 1805, Antonio de Narbona led an expedition of Spanish soldiers, accompanied by allied Native Americans, into Canyon de Chelly in the Navajo Nation to attack the Navajo tribe. When the Navajo learned of Narbona’s impending arrival, they scaled the canyon’s vertical cliffs, finding refuge in a cave where the Spanish could not reach them. Narbona’s men fired upward; bullets ricocheting from the walls of the cave took the lives of all of those inside. The cave is now known as “Massacre Cave.” Although the Spanish claimed to have taken the lives of ninety Navajo warriors in addition to twenty-five women and children, the Navajos recall the dead to have been mostly women, children, and the elderly, as the men were away hunting during the Spanish invasion.
The massacre is depicted in the Navajo pictograph in Canyon de Chelly. The image shows the Spanish cavalry wearing flat-brimmed hats and long winter capes. Soldiers on horseback carry muskets, followed by a priest wrapped in elaborate robes.
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And there is also a publication about this project, which you can find here.