Iron Nation was a principal chief of the Lower Brulé Lakota. He was one of the signers of the September 17, 1851 Treaty of Fort Laramie

Treaty of Fort Laramie (1851)

Although many European and European-American migrants to western North America had previously passed through the Great Plains on the Oregon and Santa Fe Trails, the California gold rush greatly increased traffic...

 along with people from Lakota, Cheyenne

Cheyenne

Cheyenne are a Native American people of the Great Plains, who are of the Algonquian language family. The Cheyenne Nation is composed of two united tribes, the Só'taeo'o and the Tsétsêhéstâhese .The Cheyenne are thought to have branched off other tribes of Algonquian stock inhabiting lands...

, Arapaho

Arapaho

The Arapaho are a tribe of Native Americans historically living on the eastern plains of Colorado and Wyoming. They were close allies of the Cheyenne tribe and loosely aligned with the Sioux. Arapaho is an Algonquian language closely related to Gros Ventre, whose people are seen as an early...

, and other tribes. He also signed the October 14, 1865 treaty at Fort Sully

Fort Sully

Fort Sully was one of the main military posts located on the east bank of the Missouri river in central Dakota built for use in the Indian Wars...

 with other Lakota chiefs, which established the Lower Brule Indian Reservation

Lower Brule Indian Reservation

The Lower Brulé Indian Reservation is an Indian reservation that belongs to the Lower Brulé Lakota Tribe. It is located on the west bank of the Missouri River in central South Dakota in the United States. It is adjacent to the Crow Creek Indian Reservation...

 and the 1868 Treaty

Treaty of Fort Laramie (1868)

The Treaty of Fort Laramie was an agreement between the United States and the Oglala, Miniconjou, and Brulé bands of Lakota people, Yanktonai Dakota, and Arapaho Nation signed in 1868 at Fort Laramie in the Wyoming Territory, guaranteeing to the Lakota ownership of the Black Hills, and further...

 at Fort Laramie in Wyoming

Wyoming

Wyoming is a state in the mountain region of the Western United States. The western two thirds of the state is covered mostly with the mountain ranges and rangelands in the foothills of the Eastern Rocky Mountains, while the eastern third of the state is high elevation prairie known as the High...

 which eliminated U.S. forts along the Bozeman Trail

Bozeman Trail

The Bozeman Trail was an overland route connecting the gold rush territory of Montana to the Oregon Trail. Its most important period was from 1863-1868. The flow of pioneers and settlers through territory of American Indians provoked their resentment and caused attacks. The U.S. Army undertook...

 in Montana

Montana

Montana is a state in the Western United States. The western third of Montana contains numerous mountain ranges. Smaller, "island ranges" are found in the central third of the state, for a total of 77 named ranges of the Rocky Mountains. This geographical fact is reflected in the state's name,...

 and established the Great Sioux Reservation

Great Sioux reservation

The Great Sioux Reservation was established in the Fort Laramie Treaty of 1868, and includes all of modern western South Dakota and modern Boyd County, Nebraska...

.

Chief Iron Nation also signed the Black Hills

Black Hills

The Black Hills are a small, isolated mountain range rising from the Great Plains of North America in western South Dakota and extending into Wyoming, USA. Set off from the main body of the Rocky Mountains, the region is something of a geological anomaly—accurately described as an "island of...

 agreement in September 1876. U.S. government agents went to the various Indian agencies to obtain signatures signing away Lakota rights to the Black Hills (Lakota: Paha Sapa), which the Lakota consider sacred.

The Black Hills had been guaranteed to the Lakota by the 1868 treaty signed at Ft. Laramie, but this was before gold was found, which resulted in the Black Hills Gold Rush

Black Hills Gold Rush

The Black Hills Gold Rush took place in Dakota Territory in the United States. It began in 1874 following the Custer Expedition and reached a peak in 1876-77.Rumors and poorly documented reports of gold in the Black Hills go back to the early 19th century...

.