The Holocaust was the mass murder of six million Jews and millions of other people leading up to, and during, World War II.
The killings took place in Europe between 1933 and 1945. They were organised by the German Nazi party which was led by Adolf Hitler.
The largest group of victims were Jewish people. Nearly 7 out of every 10 Jews living in Europe were killed.
Most of the victims were killed because they belonged to certain racial or religious groups which the Nazis wanted to wipe out. This kind of killing is called genocide.
The Nazis also murdered politicians, trade unionists, journalists, teachers and anyone else who spoke out against Hitler.
We will never know exactly how many died but there were many millions of non-Jewish victims, including:
- Civilians and soldiers from the Soviet Union
- Catholics from Poland
- Disabled people
- Jehovah's Witnesses
- Polish civilians
- Roma and Sinti people (Gypsies)
- Slavic people
Background information courtesy of the Holocaust Educational Trust