1865 - War on the Northern Plains

       After the treaty of Horse Creek (Fort Laramie) was violated by the U.S. Army and gold prospectors, and after the news of Sand Creek reached the ears of other tribes, the Sioux, Cheyenne and Arapaho went to war against white encroachment on their treaty-protected lands.

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        They ranged up and down the North and South Platte rivers and well into Montana and Colorado, burning stage stations, tearing down telegraph wires, halting supply trains and the mail, and effectively cutting off overland communications to Denver, Salt Lake, and San Francisco.