The Medicine Lodge Treaty is the overall name for three treaties signed near Medicine Lodge, Kansas, between the Federal government of the United States and southern Plains Indian tribes in October 1867, intended to bring peace to the area by relocating the Native Americans to reservations in Indian Territory and away from European-American settlement. The treaty was negotiated after investigation by the Indian Peace Commission, which in its final report in 1868 concluded that the wars had been preventable. They determined that the United States government and its representatives, including the United States Congress, had contributed to the warfare on the Great Plains by failing to fulfill their legal obligations and to treat the Native Americans with honesty.

The U.S. government and tribal chiefs met at a place traditional for Native American ceremonies, at their request. The first treaty was signed October 21, 1867, with the Kiowa and Comanche tribes. The second, with the Kiowa-Apache, was signed the same day. The third treaty was signed with the Southern Cheyenne and Arapaho on October 28.Under the Medicine Lodge Treaty, the tribes were assigned reservations of diminished size compared to territories defined in an 1865 treaty. The treaty tribes never ratified the treaty by vote of adult males, as it required. In addition, by changing allotment policy under the Dawes Act and authorizing sales under the Agreement with the Cheyenne and Arapaho (1890) and the Agreement with the Comanche, Kiowa and Apache (1892) signed with the Cherokee Commission, the Congress effectively further reduced their reservation territory. The Kiowa chief Lone Wolf filed suit against the government for fraud on behalf of the tribes in Lone Wolf v. Hitchcock. In 1903 the U.S. Supreme Court ruled against the tribes, determining that the Congress had "plenary power" and the political right to make such decisions. In the aftermath of that case, Congress acted unilaterally on land decisions related to other reservations as well.

Because of the outstanding issues with the treaty and subsequent government actions, in the mid-20th century, the Kiowa, Arapaho and Comanche filed several suits for claims against the U.S. government. Over decades, they won substantial settlements of monetary compensation in the amount of tens of millions of dollars, although it took years for the cases to be resolved.