|Regions with significant populations|
|English Language, Apache language|
|Christianity, Native American Church, traditional tribal religion|
|Related ethnic groups|
|Kiowa-Apache, Jicarilla Apache, Lipan Apache, Mescalero Apache, Western Apache, Navajo|
The Fort Sill Apache Tribe is headquartered in Apache, Oklahoma. Tribal member enrollment, which requires a 1⁄16 minimum blood quantum (equivalent to one great-great-grandparent), stands at 650.  The tribe continues to maintain close connections to the Chiricahua Apache who were moved to the Mescalero Apache Reservation in the late 19th century. 
Jeff Houser is the elected tribal chairman; the position has a two-year term, as do the elected tribal council positions. 
The tribal jurisdictional area, as opposed to a reservation, spans Caddo, Comanche, and Grady Counties in Oklahoma.  A private landholder returned four acres of sacred land in Cochise County, Arizona to the tribe, and it is included in their trust lands. 
Working with the US Environmental Protection Agency (EPA), in 2007 the Fort Sill Tribe began to set up an environmental protection office: to abate illegal dumping, encourage recycling, train certified water operators, and to educate the public about environmental issues. 
- Chihende (Chinde, Chihenne – ‘Red Painted People’, known as Warm Springs Apache Band or Gila Apaches, Eastern Chiricahua)
- Chukunende (Chokonende, Chokonen – ‘Ridge of the Mountainside People’, known as Chiricahua Band, proper or Central Chiricahua)
- Nde’ndai (Ndénai, Nednai, Ndé'ndai – ‘Enemy People’, ‘People who make trouble’, sometimes known as Pinery Apache Band, known as Sierre Madre Apaches, Southern Chiricahua)
- Bidánku (Bedonkohe – ‘In Front of the End People’, Bi-da-a-naka-enda – ‘Standing in front of the enemy’, sometimes known as Bronco Apache Band, known as Mogollon Apaches or Gila Apaches, Northeastern Chiricahua)
The Apache are southern Athabaskan-speaking peoples who migrated many centuries ago from the subarctic to the southwestern region of what would become the United States. The Chiricahua settled in southeastern Arizona, southwestern New Mexico of the present-day United States, and northern Sonora, and northern Chihuahua of present-day Mexico. By the late 19th century, the Chiricahua Apache territory encompassed an estimated 15 millions acres. 
In 1886 to break up the Apache Wars and resistance to European-American settlement, the US federal government took the Chiricahua into custody as prisoners of war and seized their land. The Army forcibly removed 400 members of the tribe from the Fort Apache and San Carlos Reservations in present-day Arizona,  and transported them to U.S. Army installations in Alabama and Florida.  Some warriors were held at Fort Pickens in Florida. Their ledger drawings are held in a collection by the Smithsonian Institution.
many of the Apache Scouts who serve in the capture of Geronimo were arrested by the order of General Miles forced on the same train as Geronimo was on, the Apache Scouts came from the Tonto, Pinal, Aravaipa, Apache Pecks, Chiricahua, San Carlos, White Mountain Apache bands, some of the Apache Scouts where also Apache chiefs were from different Apache bands.
In 1894, the US Congress passed a special provision to allow the Chiricahua to be relocated to Indian Territory. They were the last Indian tribe to be relocated into what is now Oklahoma.  When the Chiricahua arrived at Fort Sill, they had been promised the lands surrounding the fort as theirs to settle. Local non-Indians resisted Apache settlement, and the tribe was pressured to leave. Many wanted to return to their traditional lands in the Southwest, and the Mescalero Apache offered them land on their reservation.
A third of the Chiricahua stayed in Indian Territory, demanding that the US fulfill its promise to give them the Fort Sill lands. As a compromise, the government gave the remaining Chiricahua land which it had classified as surplus after allotment of tribal lands to individual households under the Dawes Act, on the nearby Kiowa- Comanche- Apache Reservation. In 1914, the US government finally released 84 individuals from prisoner status and granted them household allotment lands around Fletcher and Apache, Oklahoma. 
The Fort Sill Apache struggled for survival in the ensuing years in the economically depressed areas of southwestern Oklahoma. The tribe seized the opportunity afforded by Oklahoma Indian Welfare Act of 1936. Persevering through the difficulty of satisfying documentation requirements for tribal continuity, they were recognized by the federal government (Department of Interior) as a tribe in 1976. 
The first chairperson, elected in 1976, was Mildred Cleghorn, one of the last Chiricahua Apache born under "prisoner of war" status.  She was an educator and traditional doll maker, and was regarded as a cultural leader among the elders.  She served as tribal chairperson until 1995 and focused on sustaining history and traditional Chiricahua culture. 
Allan Houser was the first Fort Sill Apache child to be born free. He became one of the most celebrated Native American sculptors of the 20th century. His sons, Bob Haozous and Philip Haozous, are successful sculptors today and are both enrolled members of the tribe.
- Mildred Cleghorn (1910–1997), first chairperson of the tribe, and one of the first women elected as tribal chairperson in the United States
- Bob Haozous (b. 1943), post-modern sculptor
- Allan Houser (1914–1994), modernist sculptor and painter
- Geronimo (1829–1909), tribal leader prior to imprisonment
- 2011 Oklahoma Indian Nations Pocket Pictorial Directory. Archived May 12, 2012, at the Wayback Machine. Oklahoma Indian Affairs Commission. 2011: 15. Retrieved 3 Jan 2012.
- Coppersmith, Clifford P. "Apache Fort Sill." Oklahoma Historical Society's Encyclopedia of Oklahoma History & Culture. (retrieved 1 Feb 09)
- Turcheneske, John Anthony, Jr. "Historical Territory", Fort Sill Apache Tribe, 2003 (retrieved 1 Feb 2009)
- Closing, Jeri. "Fort Sill Apache Win Land in New Mexico." Washington Times. 23 Nov 2011. Retrieved 3 Jan 2012.
- "Casinos", 500 Nations, 2009 (retrieved 1 Feb 2009)
- 2008 Pocket Pictorial Archived April 6, 2010, at the Wayback Machine., Oklahoma Indian Affairs Commission, p. 14
- "EPA Awards Over $100,000 to the Fort Sill Apache Tribe to Develop Environmental Protection Program." EPA: United States Environmental Protection Agency. 12 Dec 07 (retrieved 1 Feb 2009)
- Everett, Dianna. "Cleghorn, Mildred Imoch (1910–1997)" Oklahoma Historical Society's Encyclopedia of Oklahoma History & Culture. (retrieved 1 Feb 09)
- Fort Sill Apache Tribe-Chiricahua Warm Springs Apache, official website
- Fort Sill Apache Industries
- "Constitution and By-Laws", Fort Sill Apache Tribe of Oklahoma