Curtis latched on to the idea that he should undertake his own grand project — to photograph every Native American nation on the continent before they disappeared. Doing such a project right required a lot of money. Curtis estimated he would need $70,000 over five years. He asked one of the wealthiest men on the planet for this huge sum — J.P. Morgan, the financier whose railroads crisscrossed Indian lands and helped accelerate the decline of their cultures.

"I like a man who attempts the impossible," Morgan told him.

Curtis worked as an ethnographer would, learning about the rituals and beliefs of each nation he visited. He might spend years returning to a reservation again and again, until he was finally granted access to sacred ceremonies, such as the Snake Dance of the Hopi. The result was a work that smashed a hateful misconception about Native Americans: that they were "godless" peoples without religious beliefs.

In the introduction to the first volume, Curtis described Native Americans as at one with "the phenomena of the universe — the trees and shrubs, the sun and stars, the lightning and rain."

"There is scarcely an act in the Indian's life that does not involve some ceremonial performance or is not itself a religious act," he wrote. In 1910, these were radical ideas for a white man to put forward.

In the end, the project took 30 years instead of five, as Curtis traveled back and forth across the U.S. some 122 times. He captured Native American life as it was, amid vast and remote landscapes, and he developed an aesthetic that influenced John Ford, Ansel Adams and many other artists.

The work, and the passion Curtis put into it, ruined his body and his marriage and left him broke. But he finished what he had proposed to Morgan: 20 volumes with 2,200 original photographs and 4,000 pages of text.

Curtis' achievement was to meld compassion with great vision, but his work was largely forgotten by the time he died in Los Angeles in 1952.

Now Egan's excellent book stands as a fitting tribute to an American original who fought for a people with his camera and his art.

hector.tobar@latimes.com