The Nazi regime frequently subjected women, both Jewish and non-Jewish, to brutal persecution that was sometimes unique to the gender of the victims. Certain individual camps and certain areas within concentration camps were designated specifically for female prisoners. In May 1939, the SS opened Ravensbrück, the largest Nazi concentration camp established for women. Over 100,000 women had been incarcerated in Ravensbrück by the time Soviet troops liberated the camp in 1945. Pregnant Jewish women and mothers of small children were sent to killing centers, where camp officials often included them in the first groups to be murdered in the gas chambers. In both camps and ghettos, women were particularly vulnerable to beatings and rape. Pregnant Jewish women often tried to conceal their pregnancies or were forced to submit to abortions. German physicians used Jewish and Roma (Gypsy) women as subjects for sterilization experiments.
Women played an important role in various resistance activities, especially those who were involved in Socialist, Communist, or Zionist youth movements. Many women escaped to the forests of eastern Poland and the Soviet Union and served in armed partisan units. Some women were leaders or members of ghetto resistance organizations. Others engaged in resistance inside the concentration camps. Five Jewish women prisoners supplied the gunpowder used to blow up a gas chamber and kill several SS men during an uprising at the Auschwitz-Birkenau killing center in October 1944. Millions of women were persecuted and murdered during the Holocaust era. However, in the end, it was their classification according to Nazi racist hierarchy or their religious and political affiliations that made them targets, not their sex.