The Navajo Nation is one of the largest tribal governments of the North American Indian Nations with a land base larger than the state of West Virginia. Its institutions include a judicial system, a legislative house, an executive office, a large law enforcement and social services apparatus, Health Services, Diné College, and other local educational trusts.
In Navajo, the geographic entity with its legally defined borders is known as "Naabeehó Bináhásdzo". This contrasts with "Diné Bikéyah" and "Naabeehó Bikéyah" for the general idea of "Navajoland". More importantly, neither of these designations should be confused with "Dinétah", the term used for the traditional homeland of the Navajo, situated in the area between the four sacred Navajo Mountains of Dookʼoʼoosłííd (San Francisco Peaks), Dibé Ntsaa (Hesperus Mountain), Sisnaajiní (Blanca Peak), and Tsoodził (Mount Taylor).
In the traditional Navajo culture, local leadership was organized around clans, which are matrilineal kinship groups. The clan leadership roles have served as a De facto government on the local level of the Navajo Nation. In 1927, agents of the U.S. federal government initiated a new form of local government entities called Chapters, modeled after government forms more familiar to the federal agents, such as counties or townships. Each Chapter elected officers and followed parliamentary procedures. By 1933, more than 100 chapters operated across the territory. The chapters served as liaisons between the Navajo and the federal government, and also acted as precincts for the elections of tribal council delegates. They also served as forums for local tribal leaders. But, the chapters had no authority within the structure of the Navajo Nation government.
Extensive uranium mining took place in areas of the Navajo Nation before environmental laws were passed or enforced on the control of hazardous wastes of such operations, or their fallout. Studies have proven the unregulated practices created severe environmental consequences for people living nearby. Several types of cancer occur at rates higher than the national average in these locations on the Navajo Nation. (Raloff, 2004) Especially high are the rates of reproductive-organ cancers in teenage Navajo girls, averaging seventeen times higher than the average of girls in the United States.