Crazy Horse was as much feared by tribal foes as he was honored by allies. His war record was unmatched by any of his peers, and his rout of Custer at the Little Bighorn reverberates through history. Yet so much about him is unknown or steeped in legend.

"Crazy Horse: A Lakota Life" corrects older, idealized accounts--and draws on a greater variety of sources than other recent biographies--to expose the real Crazy Horse: not the brash Sioux warrior we have come to expect but a modest, reflective man whose courage was anchored in Lakota piety. Kingsley M. Bray has plumbed interviews of...