With few survivors left, it’s more vital than ever to remember the Holocaust, says Sir Simon Schama

A global survey earlier this year, carried out by the Anti-Defamation League, reported that 46 per cent of those polled held anti-Semitic views. More troubling still, the misinformation, ignorance and toxic prejudice gets worse in younger generations. In that same poll, 40 per cent of those under 35 believe that Jews "are responsible for most of the world’s wars" – a view identical with Hitler's.

It has become startlingly apparent that ancient and perennial prejudices are very much alive and stalking through the present. This is evidently one of those moments when history becomes more than an academic exercise but an act of memory-preservation.

We are losing, with the passing of survivors, precious first-hand witnesses to the horrors of the Holocaust. Thankfully, much of their testimony will endure in video archive. But there is also another reason why historians must step up as memory-keepers. For even those fully aware of the Holocaust, it is mostly embodied in The Diary of Anne Frank and the death and slave labour camp of Auschwitz-Birkenau. The Holocaust, however, was much broader and deeper in its enormity.

Virtually all of Poland’s Jews – some three million – had been murdered before Auschwitz was maximally operational (nearly 900,000 at the Treblinka death camp alone).

There is a tendency to think of the mass murder as a factory extermination, the mechanical production line of death by gassing, the bodies reduced to ash. This is true, but it is only part of the dark history. Between the summer of 1941 and the spring of 1943 one and a half million Jews were shot, mostly in broad daylight, beside the mass graves into which they fell; small children buried alive under the weight of bodies.

Local populations in Lithuania – the home of my mother’s family – and in Ukraine assisted or directly executed the shootings. One site alone – Ponar Forest on the outskirts of Vilnius – counted between 70-80,000 shot Jews and ought to be as well known for its horrific atrocity as Auschwitz.

Our film, marking the 80th anniversary year of the liberation of the last concentration camps, takes you to those places of unimaginable cruelty. But conversely, it gives life and presence – voicing again the tragic eloquence and extraordinary power of those who resisted, in writing especially, knowing they were doomed but fiercely resolute that their witness should survive.

I had never been to Auschwitz, not only because my books of Jewish history were meant to be about life rather than death – to try not to reduce the whole epic of our people’s millennial story to the shedding of blood and tears. But, of course, in the case of the Holocaust, this is an impossible piety; and Auschwitz as the "metropolis of death" unavoidable.

I have always also felt that a visit could somehow never come close to the immense reality of the calamity; that somehow the experience might impose its own necessarily packaged version of the enormity. I now know I was wrong – though the sites that made me feel close to the magnitude of the bestiality were often the emptiest – the sandy avenues to the gas chambers and crematoria at Birkenau; the grove of birches where victims were stripped of clothes and the last vestiges of humanity before meeting their end.

Those places have invaded my consciousness, never to be expelled or lightened. But I will never go there again.

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Simon Schama: The Road to Auschwitz begins on Monday 7th April at 9pm on BBC Two and iPlayer.

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