Seventy-three years ago Russian troops liberated the death camp at Auschwitz - a date acknowledged since 2001 in the UK as 'Holocaust Memorial Day'.
Three months later British troops encountered their first concentration camp, Bergen-Belsen, between Hamburg and Hanover.
They found 60,000 Jews, political prisoners, PoWs and people classed as 'subhuman' by the Nazis, plus an estimated 13,000 unburied corpses.
Among the liberators of the camp was the Royal Navy's greatest pilot, Eric Brown.
A fluent German speaker who had attended the 1936 Olympics in Berlin, the Scottish aviator was asked to help with translating and interrogations of some of the camp's senior officers.
"It was utterly, utterly horrific - I've never seen such desecration of human beings," he recalled seven decades later… when he could still sense the foul stench of decomposition and decay.
In the final six months of the camp's existence, at least 35,000 prisoners died - including teenage diarist Anne Frank.
That odour came from ‘quite deep pits piled with bodies, mainly women’.
Among the living, he estimated there were 20,000 cases of typhus - inmates were dying at the rate of 500 per day - while the remaining prisoners seemed like ‘zombies - they were half dead’.
Eric Brown was asked to interrogate Belsen's former commandant, Josef Kramer, as well as the senior female guard, Irma Grese (‘probably the worst human being I ever encountered. Her trade ‘was cruelty and no form of cruelty was too much for her."), while Kramer was unrepentant, a ‘stocky bully boy’.
Both were subsequently executed for crimes against humanity. Eric Brown went on to fly more aircraft types than any other aviator, retiring from the Navy as a captain.
Such was his expertise and reputation that he was consulted on the design of today's two new aircraft carriers, HMS Queen Elizabeth and Prince of Wales.
The camp at Bergen-Belsen was eventually levelled - today nothing remains beyond the outline of the camp and a memorial site.
Nine months before his death at the age of 97, Capt Brown returned in 2015 for the 70th anniversary of its liberation, attended by the Queen and Prince Philip. Despite the passage of time he still noticed "the pall of death everywhere."
