Sir Nicholas Winton, who organised the rescue of 669 children destined for Nazi concentration camps, has died aged 106.
Sir Nicholas, then a stockbroker, arranged for trains to carry Jewish children out of occupied Prague.
The prime minister described him as a "great man" and the chief rabbi praised his "exceptional courage".
He died on the anniversary of the departure of a train in 1939 carrying the largest number of children - 241.
His son-in-law Stephen Watson said he died peacefully in his sleep at Wexham Hospital, Slough.
Sir Nicholas brought the children to Britain, battling bureaucracy at both ends, saving them from almost certain death, and then kept quiet about his exploits for a half-century.
He organised a total of eight trains from Prague, with some other forms of transport also set up from Vienna.
The Englishman who saved children from the Holocaust
- Sir Nicholas was born Nicholas Wertheimer in 1909 to Jewish parents
- By 1938 he was a young stockbroker in London
- He dropped everything to go to Prague to help Jewish refugees fleeing Nazi occupation
- Sir Nicholas organised foster families for Jewish children in Britain, placing adverts in newspapers
- The 669 children travelled on eight trains across four countries
- Sir Nicholas's team persuaded British custom officials to allow all the children in despite incomplete documentation
The reluctant hero worked to find British families willing to put up £50 to look after the boys and girls in their homes.
Sir Nicholas was knighted by the Queen in March 2003. His work has been likened to that of the "saviour" of Jewish prisoners Oskar Schindler, however it was a comparison he was not particularly fond of.
The Rotary Club of Maidenhead, of which Sir Nicholas was former president, said his daughter Barbara and two grandchildren were at his side when he died.
As a six-year-old, former Labour MP, Lord Dubs, was one of the children who was put on a train out of Czechoslovakia
He paid an emotional tribute to his rescuer as "just one of those very special human beings"
"The real fact is that he was a man who saved my life and a lot of us who came on the Kindertransport owe him an enormous debt.
"His legacy is that when there is a need for you to do something for your fellow human beings, you have got to do it," he said.
His son Nick said of his father's legacy: "It is about encouraging people to make a difference and not waiting for something to be done or waiting for someone else to do it.
"It's what he tried to tell people in all his speeches and in the book written by my sister."
Prime Minister David Cameron paid tribute to Sir Nicholas, tweeting: "The world has lost a great man. We must never forget Sir Nicholas Winton's humanity in saving so many children from the Holocaust."
Daniel Taub, Israel's ambassador to the UK, said: "He was a hero of our time, having saved 669 Jewish children from the Nazi regime. His legacy, as a point of light in an era of darkness, will forever be remembered".
Last year, Sir Nicholas was awarded the Order of The White Lion by Czech president Milos Zeman.
Michael Zantovsky, Ambassador of the Czech Republic to the United Kingdom, who was a close friend described him as "a positive man who radiated good".
"It was incredibly moving to be present at some of the gatherings of him with his so-called children and the children of his children. They all owe their existence to him."
Former prime minister Gordon Brown described Sir Nicholas as "a real hero of our times".
"Anyone who had the privilege of meeting him immediately felt admiration, respect and were in awe of his courage.
"That courage led him to risk his life to save the lives of some of the most vulnerable people. His inspiration will live on," he said.
Chief Rabbi Ephraim Mirvis praised Sir Nicholas' "exceptional courage, selflessness and modesty".
"He lived to see thousands of descendants of those whose lives he saved who were proud to call themselves members of his family, and who were inspired by his example to undertake outstanding charitable, humanitarian and educational initiatives," he said.
"I knew him to be a gentleman of unfailing old-world courtesy, with a warm heart and a ready self-deprecating wit."
Rabbi Lord Jonathan Sacks, who was Chief Rabbi of the United Hebrew Congregations of the Commonwealth from 1991 to 2013, called Sir Nicholas a "giant of moral courage" and "one of the heroes of our time".
"Our sages said that saving a life is like saving a universe. Sir Nicholas saved hundreds of universes," he said.
The Refugee Council tweeted: "Very sad to hear the news of the passing of Sir Nicholas Winton. He was an amazing man who saved many lives."
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