Nazi Germany perpetrated various crimes against humanity and war crimes against children, including the killing of children of unwanted or "dangerous" people in accordance with Nazi ideological views, either as part of their idea of racial struggle or as a measure of preventive security. They particularly targeted Jewish children in the Holocaust, but also ethnically Polish children and Romani (also called Gypsy) children and children with mental or physical disabilities. Thousands of children died in Nazi concentration camps. The Nazis and their collaborators killed children for these ideological reasons and in retaliation for real or alleged partisan attacks.
It is estimated that during World War II Nazis killed 2 million Polish and Polish Jewish children in occupied Polish territories. 1.5 million Jewish children perished in the Holocaust; tens of thousands of Romani children died in the Romani Holocaust, between 5,000 and 25,000 disabled children were killed as part of the Nazi euthanasia program. 200,000 mostly ethnic Polish children were kidnapped for the purpose of forced Germanization. Others were subject to forced labor.