HistoryData
politics1861

1861 treaty between the United States and representatives of the Cheyenne and Arapaho

February 18, 1861

This treaty ceded most Cheyenne and Arapaho lands in Colorado, but its disputed legitimacy contributed directly to the Colorado War and the Sand Creek Massacre.

Quick Facts

Year
1861
Category
politics

Key Facts

Date signed
February 18, 1861
Cheyenne chiefs who signed
6
Arapaho chiefs who signed
4
Conflict triggered
Colorado War of 1864
Notable atrocity linked
Sand Creek Massacre

By the Numbers

181,861
Date signed
6
Cheyenne chiefs who signed
4
Arapaho chiefs who signed
1,864
Conflict triggered

Location

Map of Fort Wise, United StatesMap of Fort Wise, United StatesFort Wise, United States

Cause → Event → Consequence

Cause

U.S. expansion into Colorado Territory placed increasing pressure on Southern Cheyenne and Arapaho lands. The United States sought to formally acquire these territories through a negotiated agreement, approaching a small number of tribal chiefs willing to negotiate rather than securing broad tribal consensus.

Event

On February 18, 1861, the United States concluded the Treaty of Fort Wise with six Southern Cheyenne chiefs and four Southern Arapaho chiefs, formally ceding the majority of their traditional lands in exchange for a reduced reservation. A significant portion of Cheyenne tribal members rejected the treaty, arguing it lacked legitimate authorization from the broader tribe.

Consequence

The treaty's disputed legitimacy deepened tensions between Native tribes and white settlers in Colorado. Cheyenne members who had not consented to the agreement continued using their traditional lands, creating confrontations that escalated into the Colorado War of 1864 and culminated in the Sand Creek Massacre.

Political Outcome

Outcome

Southern Cheyenne and Arapaho lands largely ceded to the United States; treaty disputed by majority of Cheyenne, fueling subsequent armed conflict.

Before

Cheyenne and Arapaho held broad territorial claims across Colorado

After

Tribes legally confined to a reduced reservation; U.S. gained formal title to ceded lands

Signatories

United States Government
Treaty party
Six Southern Cheyenne Chiefs
Cheyenne representatives
Four Southern Arapaho Chiefs
Arapaho representatives

Timeline Context

Timeline around 18611861185818591860186218631864Bombardment of Fort Sumter, immediate cause and first battle of the American Civil WarReform War — 1858–1861 internal conflict in Mexico1861 battle of the Trans-Mississippi Theater of the American Civil WarBattle between Sioux and CrowEmancipation reform of 1861 — reform passed by Tsar Alexander II of Russia which effectively abolished serfdom throughout the Russian EmpirePart of the American Civil War in New Mexico Territory (1861)1861 civil riot against Union troops during the American Civil WarBattle in the American civil wartreaty-of-fort-wise-1861