|Unorganized territory of the United States|
|o||Indian Intercourse Act||June 30, 1834|
|o||Kansas-Nebraska Act||May 30, 1854|
|o||Oklahoma Territory||May 2, 1890|
|o||Oklahoma statehood||November 16, 1907|
|Today part of||Oklahoma
Missouri (Platte Purchase)
As general terms, Indian Territory, the Indian Territories, or Indian country describe an evolving land area set aside by the United States Government for the relocation of Native Americans who held aboriginal title to their land. In general, the tribes ceded land they occupied in exchange for land grants in an area purchased by the United States federal government from Napoleonic France, the Louisiana Purchase. The concept of an Indian Territory was an outcome of the 18th- and 19th-century policy of Indian removal. After the Civil War, the policy of the government was one of assimilation.
The term Indian Reserve describes lands the British government set aside for indigenous tribes between the Appalachian Mountains and the Mississippi River in the time before the American Revolutionary War.
Indian Territory later came to refer to an unorganized territory whose general borders were initially set by the Indian Intercourse Act of 1834, and was the successor to Missouri Territory after Missouri received statehood. The borders of Indian Territory were reduced in size as various Organic Acts were passed by Congress to create incorporated territories of the United States. The 1907 Oklahoma Enabling Act created the single state of Oklahoma by combining Oklahoma Territory and Indian Territory, ending the existence of an Indian Territory.
Indian Territory, also known as the Indian Territories and the Indian Country, was land within the United States of America reserved for the forced re-settlement of Native Americans. The general borders were set by the Indian Intercourse Act of 1834. The territory was located in the Central United States.
While Congress passed several Organic Acts that provided a path for statehood for much of the original Indian Country, Congress never passed an Organic Act for the Indian Territory. Indian Territory was never an organized incorporated territory of the United States. In general, tribes could not sell land to non-Indians (Johnson v. M'Intosh). Treaties with the tribes restricted entry of non-Indians into tribal areas; Indian tribes were largely self-governing, were suzerain nations, with established tribal governments and well established cultures. The region never had a formal government until after the American Civil War. Therefore, the geographical location commonly called Indian Territory was not a traditional territory.
After the Civil War, the Southern Treaty Commission re-wrote treaties with tribes that sided with the Confederacy, reducing the territory of the Five Civilized Tribes and providing land to resettle Plains Indians and tribes of the Midwestern United States. These re-written treaties included provisions for a territorial legislature with proportional representation from various tribes.
In time, the Indian Territory was reduced to what is now Oklahoma. The Organic Act of 1890 reduced Indian Territory to the lands occupied by the Five Civilized Tribes and the Tribes of the Quapaw Indian Agency (at the borders of Kansas and Missouri). The remaining western portion of the former Indian Territory became the Oklahoma Territory.
The Oklahoma organic act applied the laws of Nebraska to the incorporated territory of Oklahoma Territory, and the laws of Arkansas to the still unincorporated Indian Territory (for years the federal court in Ft. Smith, Arkansas had jurisdiction).
The concept of an Indian territory is the successor to the British Indian Reserve, a British North American territory established by the Royal Proclamation of 1763 that set aside land for use by the Native American people. The proclamation limited the settlement of Europeans to Crown-claimed lands east of the Appalachian Mountains. The territory remained active until the Treaty of Paris (1783) that ended the American Revolutionary War, and land was ceded to the United States. The British administration reduced the land area of the Indian Reserve - the United States further reduced it after the American Revolutionary War - until it included only lands west of the Mississippi River.
At the time of the American Revolution, many Native American tribes had long-standing relationships with British who were loyal to the British Empire, but they had a less-developed relationship with the Empire's colonists-turned-rebels. After the defeat of the British, the Americans twice invaded the Ohio Country and were twice defeated. 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.
The period after the American Revolutionary War was one of rapid western expansion. The areas occupied by Native Americans in the United States were called Indian country, which was not even an unorganized territory, as the areas were established by treaty.
President Thomas Jefferson doubted the legality of the purchase. However, the chief negotiator, Robert R. Livingston believed that the 3rd article of the treaty providing for the Louisiana Purchase would be acceptable to congress. The 3rd article stated, in part:
Which committed the US government to "the ultimate, but not to the immediate, admission" of the territory as multiple states, and "postponed its incorporation into the Union to the pleasure of Congress"
After the Louisiana Purchase in 1803, President Thomas Jefferson and his successors viewed much of the land west of the Mississippi River as a place to resettle the Native Americans, so that white settlers would be free to live in the lands east of the river. Indian removal became the official policy of the United States government with the passage of the 1830 Indian Removal Act, formulated by President Andrew Jackson.
When Louisiana became a state in 1812, the remaining territory was renamed Missouri Territory to avoid confusion. Arkansas Territory, which included the present State of Arkansas plus most of the state of Oklahoma, was created out of the southern part of Missouri Territory in 1819. Originally the western border of Missouri was intended to extend due south to the Red River. However, during negotiations with the Choctaw in 1820, Andrew Jackson ceded more of Arkansas Territory to the Choctaw than he realized, resulting in a bend in the border between Arkansas and Oklahoma at Ft. Smith, Arkansas. The General Survey Act of 1824, allowed a survey that established the western border of Arkansas Territory well inside the present state of Oklahoma, where the Choctaw and Cherokee tribes had previously begun to settle. The two nations objected strongly, and in 1828 a new survey redefined the western Arkansas border. Thus, the "Indian zone" would cover the present states of Oklahoma, Kansas, Nebraska and part of Iowa. 
Before the 1871 Indian Appropriations Act, much of what was called Indian Territory was a large area in the central part of the United States whose boundaries were set by treaties between the US Government and various indigenous tribes. After 1871, the Federal Government dealt with Indian Tribes through statute; the 1871 Indian Appropriations Act also stated that. "[n]o Indian nation or tribe within the territory of the United States shall be acknowledged or recognized as an independent nation ...".
The Indian Appropriations Act also made it a federal crime to commit murder, manslaughter, rape, assault with intent to kill, arson, burglary, and larceny within any Territory of the United States. The Supreme Court affirmed the action in 1886 in United States v. Kagama, which affirmed that the US Government has plenary power over Native American tribes within its borders using the rationalization that "The power of the general government over these remnants of a race once powerful... is necessary to their protection as well as to the safety of those among whom they dwell" While the federal government of the United States had previously recognized the Indian Tribes as semi-independent, "it has the right and authority, instead of controlling them by treaties, to govern them by acts of Congress, they being within the geographical limit of the United States... The Indians [Native Americans] owe no allegiance to a State within which their reservation may be established, and the State gives them no protection." 
White settlers continued to flood into Indian country. As the population increased, the homesteaders could petition Congress for creation of a territory. This would initiate an Organic Act which established a three-part territorial government. The governor and judiciary were appointed by the President of the United States, while the legislature was elected by citizens residing in the territory. One elected representative was allowed a seat in the U. S. House of Representatives. The federal government took responsibility for territorial affairs. Later, the inhabitants of the territory could apply for admission as a full state. No such action was taken for the so-called Indian Territory, so that area was not treated as a legal territory.
The reduction of the land area of Indian Territory (or Indian Country, as defined in the Indian Intercourse Act of 1834), the successor of Missouri Territory began almost immediately after its creation with:
Indian Country was reduced to the approximate boundaries of the current state of Oklahoma by the Kansas-Nebraska Act of 1854, which created Kansas Territory and Nebraska Territory. The key boundaries of the territories were:
Kansas became a state in 1861, and Nebraska became a state in 1867. In 1890 the Oklahoma Organic Act created Oklahoma Territory out of the western part of Indian Territory, in anticipation of admitting both Indian Territory and Oklahoma Territory as a single State of Oklahoma.
At the beginning of the Civil War, Indian Territory had been essentially reduced to the boundaries of the present-day U.S. state of Oklahoma, and the primary residents of the territory were members of the Five Civilized Tribes or Plains tribes that had been relocated to the western part of the territory on land leased from the Five Civilized Tribes. In 1861, the U.S. abandoned Fort Washita, leaving the Chickasaw and Choctaw Nations defenseless against the Plains tribes. Later the same year, the Confederate States of America signed a Treaty with Choctaws and Chickasaws. Ultimately, the Five Civilized Tribes and other tribes that had been relocated to the area, signed treaties of friendship with the Confederacy.
During the Civil War, Congress gave the U.S. president the authority to, if a tribe was "in a state of actual hostility to the government of the United States... and, by proclamation, to declare all treaties with such tribe to be abrogated by such tribe"(25 USC Sec. 72). 
Members of the Five Civilized Tribes, and others who had relocated to the Oklahoma section of Indian Territory, fought primarily on the side of the Confederacy during the American Civil War in Indian territory. Brigadier General Stand Watie, a Confederate commander of the Cherokee Nation, became the last Confederate general to surrender in the American Civil War, near the community of Doaksville on June 23, 1865. 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 United States House Committee on Territories (created in 1825) was examining the effectiveness of the policy of Indian removal, which was after the war considered to be of limited effectiveness. It was decided that a new policy of Assimilation would be implemented. To implement the new policy, the Southern Treaty Commission was created by Congress to write new treaties with the Tribes siding with the Confederacy.
After the Civil War the Southern Treaty Commission re-wrote treaties with tribes that sided with the Confederacy, reducing the territory of the Five Civilized Tribes and providing land to resettle Plains Native Americans and tribes of the mid-west. General components of replacement treaties signed in 1866 include:
One component of assimilation would be the distribution of property held in-common by the tribe to individual members of the tribe.
The Medicine Lodge Treaty is the overall name given to three treaties signed in Medicine Lodge, Kansas between the US government and southern Plains Indian tribes who would ultimately reside in the western part of Indian Territory (ultimately Oklahoma Territory). The first treaty was signed October 21, 1867, with the Kiowa and Comanche tribes. The second, with the Plains Apache, was signed the same day. The third treaty was signed with the Southern Cheyenne and Arapaho on October 28.
Another component of assimilation was homesteading. The Homestead Act of 1862, was signed into law by President Abraham Lincoln. 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. Within Indian Territory, as lands were removed from communal tribal ownership, a land patent (or first-title deed) was given to tribal members. The remaining land was sold on a first-come basis (typically by land run, with settlers also receiving a land patent type deed. For these now former Indian lands, the General Land Office distributed the sales funds to the various tribal entities, according to previously negotiated terms.
The Oklahoma organic act of 1890 created an organized incorporated territory of the United States of Oklahoma Territory, with the intent of combining the Oklahoma and Indian territories into a single State of Oklahoma. The citizens of Indian Territory tried, in 1905, to gain admission to the union as the State of Sequoyah, but were rebuffed by Congress and an Administration which did not want two new Western states, Sequoyah and Oklahoma. Theodore Roosevelt then proposed a compromise that would join Indian Territory with Oklahoma Territory to form a single state. This resulted in passage of the Oklahoma Enabling Act, which President Roosevelt signed June 16, 1906. empowered the people residing in Indian Territory and Oklahoma Territory to elect delegates to a state constitutional convention and subsequently to be admitted to the union as a single state. Citizens then joined to seek admission of a single state to the Union. With Oklahoma statehood in November 1907, Indian Territory was extinguished.
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. Tribes indigenous to the present day state of Oklahoma include both agrarian and hunter-gatherer tribes. The arrival of horses with the Spanish in the 16th century ushered in horse culture-era, when tribes could adopt a nomadic lifestyle and follow abundant bison herds.
The Southern Plains villagers, an archaeological culture that flourished from 800 to 1500 CE, lived in semi-sedentary villages throughout the western part of Indian Territory, where they farmed maize and hunted buffalo. They are likely ancestors of the Wichita and Affiliated Tribes. 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 early Wichita people were hunters and gatherers who gradually adopted agriculture. By about 900 CE, farming villages began to appear on terraces above the Washita River and South Canadian River in Oklahoma.
Member tribes of the Caddo Confederacy lived in the eastern part of Indian Territory and are ancestors of the Caddo Nation. The Caddo people speak a Caddoan language and is a confederation of several tribes who traditionally inhabited much of what is now East Texas, northern 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 BCE. In an 1835 Treaty  made at the agency-house in the Caddo nation and State of Louisiana, the Caddo Nation sold their tribal lands to the US. In 1846 the Caddo along with several other tribes signed a treaty that made the Caddo a protectorate of the US and established framework of a legal system between the Caddo and the US. Tribal headquarters are in Binger, Oklahoma.
The Wichita and Caddo both spoke Caddoan languages, as did the Kichai people, who were also indigenous to what is now Oklahoma and ultimately became part of the Wichita and Affiliated Tribes. The Wichita (and other tribes) signed a treaty of friendship with the US in 1835. The tribe's headquarters are in Anadarko, Oklahoma.
In the 18th century, prior to Indian Removal (the forced relocation by the US federal government) Kiowa, Apache, and Comanche people entered into Indian Territory from the west, and the Quapaw and Osage entered from the east. During Indian Removal of the 19th century, additional tribes received their land either by treaty via land grant from the federal government of the United States or they purchased the land receiving fee simple recorded title.
Many of the tribes forcibly relocated to Indian Territory were from Southeastern United States, including the so-called Five Civilized Tribes or Cherokee, Chickasaw, Choctaw, Muscogee Creeks, and Seminole, but also the Natchez, Yuchi, Alabama, Koasati, and Caddo people.
Between 1814 and 1840, the Five Civilized Tribes had gradually ceded most of their lands in the Southeast section of the US through a series of treaties. The southern part of Indian Country (what eventually became the State of Oklahoma) served as the destination for the policy of Indian removal, a policy pursued intermittently by American presidents early in the 19th century, but aggressively pursued by President Andrew Jackson after the passage of the Indian Removal Act of 1830. The Five Civilized Tribes in the South were the most prominent tribes displaced by the policy, a relocation that came to be known as the Trail of Tears during the Choctaw removals starting in 1831. 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. Other tribes, such as the Delaware, Cheyenne, and Apache were also forced to relocate to the Indian territory.
The Five Civilized Tribes established tribal capitals in the following towns:
These tribes founded towns such as Tulsa, Ardmore, Muskogee, which became some of the larger towns in the state. They also brought their African slaves to Oklahoma, which added to the black American population in the state.
The Western Lakes Confederacy was a loose confederacy of tribes around the Great Lakes region, organized following the American Revolutionary War to resist the expansion of the United States into the Northwest Territory. Members of the confederacy were ultimately removed to the present-day Oklahoma, including the Shawnee, Delaware (also called Lenape), Miami, and Kickapoo.
The Council of Three Fires is an alliance of the Ojibwe, Odawa, and Potawatomi tribes. 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 to Kansas and Nebraska, and ultimately to Oklahoma.
The Illinois Potawatomi moved to present-day Nebraska and the Indiana Potawatomi moved to present-day Osawatomie, Kansas, an event known as the Potawatomi Trail of Death. The group settling in Nebraska adapted to the Plains Indian culture but the group settling in Kansas remained steadfast to their woodlands culture. In 1867 part of the Kansas group negotiated the "Treaty of Washington with the Potawatomi" in which the Kansas Prairie Band Potawatomi Nation split and part of their land in Kansas was sold, purchasing land near present-day Shawnee, Oklahoma, they became the Citizen Potawatomi Nation.
The Odawa tribe first purchased lands near Ottawa, Kansas, residing there until 1867 when they sold their lands in Kansas and purchased land in an area administered by the Quapaw Indian Agency in Ottawa County, Oklahoma, becoming the Ottawa Tribe of Oklahoma.
The Peoria tribe, native to southern Illinois, moved south to Missouri then Kansas, where they joined the Piankashaw, Kaskaskia, and Wea tribes. Under stipulations of the Omnibus Treaty of 1867, these confederated tribes and the Miami tribe left Kansas for Indian Territory on lands purchased from the Quapaw.
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. In pre-revolutionary war days, their confederacy expanded to areas from Kentucky and Virginia north. All of the members of the Confederacy, except the Oneida and Tuscarora, allied with the British during the Revolutionary War, and were forced to cede their land after the war. Most moved to Canada after the Treaty of Canandaigua in 1794, some remained in New York, and some moved to Ohio, joining the Shawnee.
The 1838 and 1842 Treaties of Buffalo Creek were treaties with New York Indians, such as the Seneca, Mohawk, Cayuga, and Oneida Indian Nation, which covered land sales of tribal reservations under the US Indian removal program, by which they planned to move most eastern tribes to Indian Territory. Initially, the tribes were moved to the present state of Kansas, and later to Oklahoma on to land administered by the Quapaw Indian Agency.
Western Indian Territory is part of the Southern Plains and is the ancestral home of the Wichita people, a Plains tribe. Additional indigenous peoples of the Plains entered Indian Territory during the horse culture era. Prior to adoption of the horse, some Plains Indian tribes were agrarian and others were hunter-gatherers. Some tribes used the dog as a draft animal to pull small travois (or sleighs) to help move from place to place; however, by the 18th century, many Southern Plains tribes adopted the horse culture and became nomadic. 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.
Historically, the Arapaho 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. Kiowa and Comanche controlled a vast expanse of territory from the Arkansas River to the Brazos River. By 1840 many plains tribes had made peace with each other and developed Plains Indian Sign Language as a means of communicate with their allies.
After the Modoc War from 1872 to 1873, Modoc people were forced from their homelands in southern Oregon and northern California to settle at the Quapaw Agency, Indian Territory. The federal government permitted some to return to Oregon in 1909. Those that remained in Oklahoma became the Modoc Tribe of Oklahoma.
During the Reconstruction Era, when the size of Indian Territory was reduced, the renegotiated treaties with the Five Civilized Tribes and the tribes occupying the land of the Quapaw Indian Agency contained provisions for a government structure in Indian Territory. Replacement treaties signed in 1866 contained provisions for:
In a continuation of the new policy, the 1890 Oklahoma organic act extended civil and criminal laws of Arkansas over the Indian Territory, and extended the laws of Nebraska over Oklahoma Territory.