After American militias massacred Cheyenne and Arapaho as part of the Civil War in the West, indigenous warriors banded together, determined to not let American colonizers’ unwarranted violence go unanswered.

In January 1865, Julesburg, Colorado was 200 miles east of Denver. Complete with an eating-house, stable, blacksmith, repair shop, granary, and corral, the town was an important waystation for immigrants and settlers traveling along the Platte River on the Oregon Trail.

However, Julesburg’s relative prominence also made it a target for Native retaliation after the Sand Creek Massacre. Six weeks earlier, on November 29, 1864, led by brevet Colonel John Chivington, the 675-men strong Third Colorado massacred several hundred Cheyenne and Arapaho men, women, and children in southeastern Colorado Territory. Dog Soldiers (a militant Cheyenne subgroup) allied with other Cheyenne, Arapaho, and Lakota warriors to avenge their relatives who died at Sand Creek. In total, they numbered some 1200 Dog Soldiers and other warriors. Sitting Bull, Spotted Tail, Pawnee Killer, and others led the attack on Julesburg. On January 7, 1865, the allied Natives found that many soldiers had left town as part of their regular patrols, leaving only 37 men to defend the fort at Julesburg.

A small group of Lakotas led the initial charge. Nicholas James O’Brien, a highly decorated Civil War soldier and commander of the troops at Julesburg, saw the oncoming attack and pursued the Lakotas, unwittingly falling into their strategic trap to encircle the soldiers once they had been separated from reinforcements. The Native alliance intended to surround the American soldiers, but some young Cheyenne left their position too early before the entrapment could be realized. Despite this minor lapse, within a few minutes of fighting, nearly half of the U.S. soldiers were killed.

O’Brien led his surviving soldiers back to the fort, and the Native alliance laid siege. The remaining tribesmen entered Julesburg and raided every building. George Bent, a Cheyenne who participated in the raid, recalled that allied Natives found all the goods they desired. Tribal women brought extra horses to carry the spoils back to their camps. The horses were so heavily loaded that it took three days to make the return trip home. The raid lasted the whole day and became the first of many Cheyenne, Arapaho, and Lakota raids conducted in the Central Plains over the coming months. The accumulation of goods brought sustenance to the tribes that winter while the United States took a staggering blow to their efforts to control American Indian affairs during the Civil War.


Battle of Julesburg
Battle of Julesburg An illustration of Julesburg at the time of the raid. Source:

“Burning of Julesburg, C.T.” ca. 1865. Courtesy of Denver Public Library Special Collections (X-9613).

George Bent
George Bent George Bent, a Cheyenne who participated in the Native alliance’s attack, with his wife Magpie. Source:

“George Bent and Magpie.” 1867. Via Wikimedia Commons (public domain).

Sitting Bull
Sitting Bull A portrait of Sitting Bull, who took part in the Battle of Julesburg. Source: “Sitting Bull.” D.F. Frances, ca. 1880–1888. Courtesy of the History Colorado Online Collection (94.163.12).
Dog Soldier artwork
Dog Soldier artwork This drawing, made by a Dog Soldier, may depict O’Brien fleeing from the Cheyenne warriors who sprung the encirclement trap too early in the Battle of Julesburg. Source: Dog Soldier ledger book; Summit Springs sketch book. Ca. 1860–1869. Courtesy of the Colorado History Online Collection (84.37.1).


114 E 1st St, Julesburg, CO 80737 | This marks the Fort Sedgwick Museum, a museum for the fort which the Dog Soldiers, Cheyenne, Arapaho, and Lakota laid siege to in the Battle of Julesburg.


Ryan Blamires, Brigham Young University, “Battle of Julesburg,” Intermountain Histories, accessed April 15, 2024,