Fort Union

Along the Santa Fe Trail

Nestled on the rolling plains of northeastern New Mexico, Fort Union stands as a testament to the history of the American Old West. Established in April 1851, this military outpost helped to shape the future of the region and the nation. 

When New Mexico entered the Union after the Mexican-American War, the U.S. army began to establish garrisons in different towns along the Rio Grande River. In 1851, Lt. Col. Edwin V. Sumner was ordered by the Secretary of War, C.M. Conrad, "to revise the whole system of defense" for the area. He relocated these scattered garrisons to posts closer to Native American tribes. Fort Union was originally founded to protect the Santa Fe Trail, a vital trade route connecting Missouri to Santa Fe. The fort underwent three iterations, in 1851, 1861, and the final and largest version constructed in 1862. Its strategic location made it a crucial hub for military operations, serving as a supply depot, logistical center, and headquarters for campaigns against Native American tribes and Confederate forces. 

The first version of the fort was built to protect nearby habitants and travelers along the Santa Fe Trail from hostile Native American tribes. It was a place where soldiers could be fed and housed. The second version of the fort became a more traditional defense fort to keep Confederate troops out. Soldiers from Fort Union participated in the Battle of Glorieta Pass. During the Civil War, Fort Union played a key role in securing the Southwest for the Union. And preventing the Confederate forces from gaining access to the west. The fort became a crucial supply depot for Union forces, ensuring the flow of goods and personnel to sustain campaigns against Confederate and Confederate-aligned Native American forces to the region.  

In the 1870s Fort Union was the headquarters for the 8th Calvary as well as the 9th Calvary later. The third and final fort was abandoned due to the gradual construction of the Santa Fe Railroad. The fort was eventually decommissioned in 1891 and left to the elements. In 1956, Fort Union National Monument was established to preserve and interpret the history of this significant site. The reconstructed officer’s quarters, enlisted men’s barracks, and the hospital offer visitors a tangible connection to the daily lives of soldiers there. 

Fort Union, New Mexico, stands as both a physical and historical landmark, providing a window into the complex and often tumultuous history of the American West. Today visitors can view the preserved second of the three forts, as well as various ruins of the third.  

Related Battles

Santa Fe County and San Miguel County, NM | March 26, 1862
Result: Union Victory
Estimated Casualties
Valverde, New Mexico | February 21, 1862
Result: Confederate Victory
Estimated Casualties