The use of slave and forced labour in Nazi Germany and throughout German-occupied Europe during World War II took place on an unprecedented scale. It was a vital part of the German economic exploitation of conquered territories. It also contributed to the mass extermination of populations in occupied Europe. The Germans abducted approximately 12 million people from almost twenty European countries; about two thirds came from Central Europe and Eastern Europe. Many workers died as a result of their living conditions – extreme mistreatment, severe malnutrition and abuse were the main causes of death. Many more became civilian casualties from enemy (Allied) bombing and shelling of their workplaces throughout the war. At the peak of the program the forced labourers constituted 20% of the German work force. Counting deaths and turnover, about 15 million men and women were forced labourers at one point during the war.

Forced labour, or unfree labour, is any work relation, especially in modern or early modern history, in which people are employed against their will with the threat of destitution, detention, or violence, including death or other forms of extreme hardship to either themselves or members of their families.