1300 to 1000 years ago--Athabascan migration to the Pacific Coast. 1000 to 600 years ago--Apachean migration to the Southwest. 500 to 400 years ago--Beginnings of the differentiation of contemporary Apachean tribes ( Hoijer 1956:232).

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The Navajo and Hopi Reservations together comprise 15,087,163 acres or 23,574 square miles on the Colorado Plateau, an area that straddles the divide separating the watershed of the San Juan and Little Colorado Rivers. Four principal regions can be distinguished: the flat alluvial valleys at elevations from 4,500 to 6,000 feet; upland plains between 5,500 and 7,000 feet; mesas at from 6,000 to 8,000 feet; and mountains from 7,500 to over 10,000 feet in altitude. Each of these regions is cut by canyons ranging from a few hundred to 2,000 feet in depth. Most of the area lies between 5,000 and 7,000 feet in altitude.

The Navajo Nation encompasses portions of Arizona, New Mexico, and Utah, covering over 25,000 square miles of land.

The Authority Systems of the Federal Government
and the Local States

THE FEDERAL authority system as it affects Indian affairs is easier to analyze than the traditional Navajo system because of its formal structure.

It is, in Weber's terms, a rational-legal system in which obedience is owed to a legally established order.

Concrete units and offices are impersonally defined and delimited. At the level that most directly touches the Navajo systems, the Bureau of Indian Affairs, there is a complete bureaucracy with regular activities distributed as official duties.

Power is hierarchical and authoritarian, accepted by voluntary submission, or imposed by sanctions that are adjudicated in formal courts and enforced by an apparatus of police, prisons, and a national army.

The validity of Federal claims to obedience rests on rational grounds, on normative rules defining the right of those elevated to authority to issue commands.

The Basis for Authority over Indian Affairs

Felix Cohen says that the Constitution of the United States forms the basis for Federal control over Indian affairs, since the national government derives its sovereignty from powers delegated to it by the states (Cohen 1942:89). Rice, as quoted by Cohen, details the principal sources of the authority Congress exercises over the Indians:

In view of the express grants of the commerce power and the expenditure-for-thegeneral-welfare-power, of the fact that the greater Indian tribes lived on the national domain and not within any state (until the west was piece-meal admitted to statehood) and of the custom of dealing with Indian tribes by treaty, the United States Supreme Court has never found, so far as I can learn, that any Congressional regulation of Indians has been beyond the reach of the national power. Indeed the net result is the creation of a new power, a power to regulate Indians ( Cohen 1942:89).


OUR UNDERSTANDING of some of the main problems facing the Navajo Tribal Council and the U.S. Government in its relations with the tribe depends in part on a knowledge of the natural setting and natural resources of the Reservation.

One key question is the number of people the Reservation can be expected to support if, and when, it is developed to maximum capacity by means of irrigation, the establishment of industries on tribal land or on the periphery, the development of tourist business, the control of grazing practices, and the exploitation of timber and mineral resources.

Conditions of the natural setting also bear on the problem of whether to allot tribal land to individuals or to encourage the collective development of Reservation resources.

Three distinct climates are to be found within the Navajo Reservation: the cold humid climate of the heights; the steppe climate of the mesas and the high plains; and the comparatively warm desert, including the lower portions of the Chaco and Chinle Valleys and all of the southern, western, and northwestern parts of the Reservation. Eight percent of the area is classed as humid; 37 per cent as steppe; and 55 percent as desert.

Temperatures in the humid zone average from 43 to 50 degrees, with a low of 4 degrees and a high of 80. The annual rainfall there is from 16 to 27 inches, and the growing season averages 95 days. The steppe zone has an annual temperature range from 45 to 50 degrees with a low of 10 degrees and a high of 88. Annual rainfall is from 12 to 16 inches, and the growing season averages 147 days.

Finally, the desert-zone temperatures average 50 to 60 degrees, with a low of 11 degrees and a high of 110. Annual rainfall is between 7 and 11 inches, and the growing season averages 173 days.

Source: Navajo Ways in Government: A Study in Political Process. Contributors: Mary Shepardson - author. Publisher: American Anthropological Association. Place of Publication: Menasha, WI. Publication Year: 1963.