Ravensbrück, recalled Denise Dufournier, a prisoner at the camp, was "like a mysterious planet, where the macabre, the ridiculous, and the grotesque rubbed shoulders in a fantastic irrational chaos." The only concentration camp designed specifically for women by the Nazis, Ravensbrück "accommodated" about 125,000 individuals from 1939 to 1945.

About 10 percent of them were Jewish. The rest included political prisoners (communists and anti-Nazis), "asocials" (prostitutes and lesbians), Jehovah's Witnesses, Gypsies, Poles, Russians, French and a scattering of other nationalities.

Some 40,000 or 50,000 prisoners died there, many of them gassed or shot in a desperate effort by the Nazis to cover up what they had done before the Russian Army liberated the camp.

In "Ravensbrück," Sarah Helm, a former reporter and feature writer for the Sunday Times of London, draws on material released from archives in Eastern Europe after the end of the Cold War and interviews with survivors to provide a remarkable and riveting account of the social structure of the camp: the SS men, guards and kapos who were willing to use human beings as slaves and kill them when they couldn't work anymore, and the prisoners themselves, whose names and voices "are more important than their numbers."

Helm insists that we confront the monstrous cruelty — beatings, starvation and random executions — that was part of daily life at Ravensbrück. She describes in graphic detail the bone and muscle experiments performed on 54 Polish prisoners, who were injected with bacteria, pieces of glass and splinters and then operated on. She reveals the role of the International Committee of the Red Cross in "hushing up" revelations about these women, known as "the Ravensbrück rabbits." And she documents the complicity of Siemens and other corporations in the use of slave labor in munitions plants.

As she gives names to "the nameless things done to women's bodies," Helm reminds us that extraordinary acts of courage often occurred at Ravensbrück. Several of the "rabbits" devised secret writing to inform outsiders about the experimental operations; they also delivered a statement of protest to the chief guard at Ravensbrück.

Russian women working at a factory "sub camp" inserted the bullet ignition into the cartridge cases upside down; when spot checks confirmed that all the bullets had failed, the saboteurs were hanged. And Helm provides example after example of women who risked their lives by interceding with a guard to stop a beating or by hiding a sick or disabled friend who had been scheduled for extermination.

Ravensbrück, Helm concludes, "should have shaken the conscience of the world." She has done a signal service in giving the camp "its rightful name and place in history."

Glenn C. Altschuler is the Thomas and Dorothy Litwin professor of American Studies at Cornell University.