Ben Helfgott, one of Britain's best known Holocaust survivors who represented the country twice as an Olympic weightlifter, died on Friday aged 93.
The Holocaust Educational Trust, one of the education charities with which Helfgott was associated, paid tribute to "a giant amongst men".
"Ben survived the worst of humanity. His legacy is the ultimate triumph over that darkness," Prime Minister Rishi Sunak tweeted.
Helfgott was born in Poland in 1929. His Jewish family were forced into a ghetto when the Nazis invaded the country at the outset of World War II.
He survived brutal conditions in two concentration camps and a labour camp, but lost almost all his relatives to the genocide, and came to Britain alone after the war aged 15.
In 1948, Helfgott walked past a group of young men lifting weights on London's Hampstead Heath, and asked to try.
By 1956, he was captaining the British weightlifting team at the Melbourne Olympics, and also competed in the 1960 Rome Games. He won bronze at the 1958 Commonwealth Games in Cardiff.
Throughout his life, Helfgott worked to maintain awareness of the Holocaust, including in 2012 when he gave a talk to England's football team before they visited Auschwitz.
"Despite all he endured, Ben taught us all about resilience, tolerance and the crucial importance of educating future generations," Holocaust Educational Trust chief executive Karen Pollock said.
"He was our friend and mentor, and we mourn his loss deeply."
Chief Rabbi Ephraim Mirvis hailed him as "one of the most inspirational people I have known".
Helfgott was knighted in 2018, for services to Holocaust remembrance and education.
Opposition Labour party leader Keir Starmer noted that Helfgott was one of only two known Holocaust survivors who went on to compete in the Olympics.
"Throughout his life, Sir Ben demonstrated compassion and understanding, campaigning for tolerance and peaceful coexistence between communities," Starmer said.
"These are values by which we should all live. His life and legacy will be an inspiration to us all," he said.
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