Answer:
A gold strike at Pikes Peak in Colorado sent miners swarming to the region.
Explanation:
The Treaty of Fort Laramie (also called the Sioux Treaty of 1868) was an agreement between the United States and the bands Oglala, Miniconjou, and Brulé of the Lakota, Yanktonai Dakota and the Arapaho Nation signed in 1868 at Fort Laramie in the Territory of Wyoming , which guarantees the Lakota, owned by the Black Hills, land and hunting rights in South Dakota, Wyoming and Montana. The territory of the Powder River was going to be closed from now on to all the whites. The treaty ended the Red Cloud War.
Repeated violations of the other exclusive rights to the land of gold prospectors led to the Black Hills War. Migrant workers in search of gold had crossed reserve borders, violating the treaty. The Indians had assaulted the gold prospectors, violating the treaty, and the war broke out. The US government He seized the land of the Black Hills in 1877.