The term "Indian country" is used to signify lands under the control of Native nations, including Indian reservations, trust lands on Oklahoma Tribal Statistical Area, or, more casually, to describe anywhere large numbers of Native Americans live.

The territory remained active until the Treaty of Paris that ended the American Revolutionary War, and the land was ceded to the United States.

They finally defeated the Indian Western Confederacy at the Battle of Fallen Timbers in 1794, and imposed the Treaty of Greenville, which ceded most of what is now Ohio, part of present-day Indiana, and the lands that include present-day Chicago and Detroit, to the United States federal government.

In 1803, the United States agreed to purchase France's claim to French Louisiana for a total of $15 million (less than 3 cents per acre).

But this was part of the negotiated lands of Lovely's Purchase where the Cherokee, Choctaw, Creek and other tribes had been settling, and these indian nations objected strongly.

[6] After these redefinitions, the "Indian zone" would cover the present states of Oklahoma, Kansas, Nebraska and part of Iowa.

[8][9][10][11] The Indian Appropriations Act also made it a federal crime to commit murder, manslaughter, rape, assault with intent to kill, arson, burglary, or larceny within any Territory of the United States.

The governor and judiciary were appointed by the President of the United States, while the legislature was elected by citizens residing in the territory.

Some in federal leadership, such as Secretary of State William H. Seward, did not believe in the rights of Indians to continue their separate tribal governments, and vocally championed opening the area to white settlement while campaigning for Abraham Lincoln in 1860.

[14] Some historians argued Seward's words steered many tribes, notably the Cherokee[15] and the Choctaw[16] into an alliance with the Confederate States.

The Reconstruction Treaties signed at the end of the Civil War fundamentally changed the relationship between the tribes and the U.S. government.

The Reconstruction era played out differently in Indian Territory and for Native Americans than for the rest of the country.

In 1862, Congress passed a law that allowed the president, by proclamation, to cancel treaties with Indian Nations siding with the Confederacy (25 USC 72).

The Act gave an applicant freehold title to an area called a "homestead" – typically 160 acres (65 hectares or one-fourth section) of undeveloped federal land.

However, in 2020, the United States Supreme Court prompted a review of tribal lands through its decision in McGirt v. Oklahoma.

Indian Territory marks the confluence of the Southern Plains and Southeastern Woodlands cultural regions.

Its western region is part of the Great Plains, subjected to extended periods of drought and high winds, and the Ozark Plateau is to the east in a humid subtropical climate zone.

The ancestors of the Wichita have lived in the eastern Great Plains from the Red River north to Nebraska for at least 2,000 years.

The Caddo people speak a Caddoan language and is a confederation of several tribes who traditionally inhabited much of what is now East Texas, North Louisiana, and portions of southern Arkansas, and Oklahoma.

The tribe was once part of the Caddoan Mississippian culture and thought to be an extension of woodland period peoples who started inhabiting the area around 200 BC.

The trail ended in what is now Arkansas and Oklahoma, where there were already many Indians living in the territory, as well as whites and escaped slaves.

Members of the confederacy were ultimately removed to the present-day Oklahoma, including the Shawnee, Delaware, also called Lenape, Miami, and Kickapoo.

In the Second Treaty of Prairie du Chien in 1829, the tribes of the Council of Three Fires ceded to the United States their lands in Illinois, Michigan, and Wisconsin.

The 1833 Treaty of Chicago forced the members of the Council of Three Fires to move first to present-day Iowa, then Kansas and Nebraska and ultimately to Oklahoma.

[39] The Iroquois Confederacy was an alliance of tribes, originally from the Upstate New York area consisting of the Seneca, Cayuga, Onondaga, Oneida, Mohawk, and, later, Tuscarora.

Initially, the tribes were moved to the present state of Kansas, and later to Oklahoma on land administered by the Quapaw Indian Agency.

Additional indigenous peoples of the Plains entered Indian Territory during the horse culture era.

The tipi, an animal hide lodge, was used by Plains Indians as a dwelling because they were portable and could be reconstructed quickly when the tribe settled in a new area for hunting or ceremonies.

The Arapaho historically had assisted the Cheyenne and Lakota people in driving the Kiowa and Comanche south from the Northern Plains, their hunting area ranged from Montana to Texas.

[46] The Nez Perce, a Plateau tribe from Washington and Idaho, were sent to Indian Territory as prisoners of war in 1878, but after great losses in their numbers due to disease, drought and famine, they returned to their northwestern homelands in 1885.