Welcome to the History Extra podcast, fascinating historical conversations from the makers of BBC History Magazine.

Between 1939 and 1945, the Nazis killed nearly 300,000 people with psychiatric illnesses or cognitive disabilities.

Some 400,000 more were forcibly sterilized.

Historian Dagmar Herzog's book, The Question of Unworthy Life,

examines how decades of eugenic theorising and anti-disability propaganda

led so many people and institutions to become complicit in this program of sterilisation and

mass murder and explores why it took Germany so long to fully recognise it as a crime.

I spoke to Dagmar to find out more.

Before we get into anything else, I wonder if we can start with the central event of your book.

What exactly was the Nazi's so-called euthanasia program and who did it target?

So the Nazis killed approximately 300,000 people on grounds that this was a mercy death,

in quotes, euthanasia, that is a euphemism, because in fact they were grotesque and cruel deaths.

And the people they targeted were primarily those who were either having diagnoses of psychiatric

illness, predominantly schizophrenia, although that was a huge umbrella term, or they were people

with cognitive deficiencies. And above all, they were the long-term institutionalized, and they were

people who could not work. They required the care of others, and that is why they

were targeted for death. So it's predominantly people who have cognitive impairments or psychiatric

illness or behavioral disturbances. It is sometimes also people with physical disabilities,

but predominantly it's emotional and intellectual disabilities.

And that's really important to understand because it's kind of been tabooized and the sort of vague general term of disability has been used.

But we need to understand that it's people who were so disabled that they could not work.

It could not contribute and that is why they were targeted.

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