There is considerable scholarly debate regarding the size of America's native population in 1492  (When Columbus "Discovered" America)   A modest estimate is that 75 million people occupied North and South America at the time of Columbus's voyages, a figure that represents approximately 15 percent of the world's population at that time.

Most of these people lived south of the Rio Grande, in what is today central Mexico and some of the countries that form Central and South America.   The native population of aboriginal America north of Mexico has been estimated at anywhere from less than 1 million to as many as 18 million.

What accounted for such a decline in the face of remarkable population growth of the groups who colonized North America after 1492?   An important reason for the Native American holocaust were the diseases the Europeans and Africans brought with them to North America;  other reasons included war, genocide, the destruction of traditional ways of life, and forms of colonial rule that both reduced native populations and prevented normal recovery.

In the early 1980s the total membership of the three hundred recognized U.S. tribes was about 900,000.

Tribal Census 1999 Top thirty tribes only

1 Cherokee 308,132

2 Navajo 219,198

3 Chippewa 103,826

4 Sioux 103,255

5 Choctaw 82,299

6 Pueblo 52,939

7 Apache 50,051

8 Iroquois 49,038

9 Lumbee 48,444

10 Creek 43,550

11 Blackfoot 32,234

12 Canadian & Latin Americ. 22.379

13 Chickasaw 20,631

14 Potawatomi 16,763

15 Tohono O' Odham 16,041

16 Pima 14,431

17 Tlingit 13,925

18 Seminole 13,797

19 Alaskan Athabaskans 13,738

20 Cheyenne 11,456

21 Comanche 11,322

22 Paiute 11,142

23 Puget Sound Salish 10,246

24 Yaqui 9,931

25 Osage 9,527

26 Kiowa 9,421

27 Delaware 9,321

28 Shoshone 9,215

29 Crow 8,588

30 Cree 8,290