In 1906, Curtis was financed by J.P. Morgan who wanted to fund a documentary expedition to capture the lives and memories of indigenous tribal people. With Morgan's support, Curtis spent 20 years traveling the North American continent and captured 40,000 images of 80 different tribes.

These are 12 of his best photos.

Nakoaktok dancers wear Hamatsa masks in a ritual, 1914

Piegan chiefs, 1900

A Maricopa woman, 1907

Okuwa-Tsire, also known as "Cloud Bird," of the San Ildefonso Pueblo, 1905

A Maricopa woman with arrow-brush stalks. 1907

An Apsaroke shaman, 1908

A Cahuilla woman, 1924

A Kwakiutl chief's daughter, 1910

A Kutenai duck hunter, 1910

Medicine Crow, of the Apsaroke tribe, 1908

A Wishran girl, 1910

Nesjaja Hatali, Navajo medicine man, 1904

Members of the Qagyuhl tribe dance to restore an eclipsed moon, 1910