The man who saved a generation: More than two dozen Jewish children rescued from the clutches of the Nazis join Theresa May at memorial service for Holocaust hero

More than two dozen Jewish children saved from the clutches of the Nazis on the eve of the Second World War have gathered to pay tribute to their rescuer at a memorial service.

In the months leading up to the outbreak of war in September 1939, Sir Nicholas Winton worked tirelessly to bring 669 Jewish children from Nazi-occupied Czechoslovakia to safety in Britain.

After the war, Sir Nicholas lived in relative anonymity, enjoying a quiet life with his Danish-born wife Grete and their three children in Maidenhead, Berkshire.

His wartime bravery remained a secret for decades. Then, in 1988, his incredible story was shared on That's Life, hosted by Dame Esther Rantzen, and Sir Nicholas was soon hailed a national hero.

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Paying tribute: Home Secretary Theresa May speaks at the memorial service for Sir Nicholas Winton at the Old Library at the Guildhall, central London today. She said she felt privileged to have known Sir Nicholas

Memorial: More than two dozen Jewish children saved from the clutches of the Nazis on the eve of the Second World War gathered to pay tribute to their rescuer, Sir Nicholas Winton, in a service at London's Guildhall today

Recognition: Sir Nicholas Winton, receiving the Order of White Lion, the Czechs' highest honour, in 2014

Dubbed 'Britain's Oskar Schindler' - after the German industrialist who saved more than 1,000 Jews - Nicholas was knighted by the British Government, awarded the Czechs' highest honour, and even nominated for the Nobel Peace Prize.

Last year, at the age of 106, Sir Nicholas died peacefully in his sleep at Wexham Park Hospital, Slough, with his daughter Barbara and two grandchildren at his side.

Today, hundreds attended a service at London's Guildhall to celebrate his life, including Dame Esther, representatives from the Czech and Slovak authorities and the British Government, and former Labour MP Lord Dubs who was another of the children saved by Sir Nicholas's actions.

Home Secretary Theresa May, MP for Maidenhead, where Sir Nicholas lived, also joined Czech and Slovak officials at the Guildhall in London on what would have been Sir Nicholas's 107th birthday.

Survivors from as far as Israel, America and the Czech Republic attended the service alongside descendants of some of those who have since died, to commemorate the life of a man they say they owe their lives to.

Among the rescued 'children' to pay tribute was Lord Dubs, who was six years old when his mother put him on one of the eight trains which carried the young people to Britain.

Family: Nick and Barbara Winton, the son and daughter of Sir Nicholas, both spoke at their father's service

Saved from the Nazis: Among the rescued 'children' to pay tribute was Lord Alfred Dubs (pictured), who was six years old when his mother put him on one of the eight trains which carried the young people to Britain

The former Labour MP, who came to consider Sir Nicholas a friend when they met in later life, said he had had the 'tenacity and willpower' to take action against the problems facing people in Prague.

He said: 'He tackled them with determination and he did it. He could've walked away but he didn't, and to him many of us owe our lives.'

Sir Nicholas, known affectionately as Nicky by his family, lived a life full of 'love, laughter, passion and commitment', his daughter Barbara said.

Considering the families many of the children went on to have, Sir Nicholas's relatives estimate somewhere in the region of 7,000 people were able to live because of what he did.

Among his many honours were an MBE in 1983 for his services to learning disability charity Mencap, a knighthood in 2003 for services to humanity, and the awarding of a Hero of the Holocaust medal at 10 Downing Street in 2010.

Dame Esther Rantzen, whose That's Life programme in 1988 brought Sir Nicholas's story to public attention, recreated the moment he first met those he had saved.

The clip showing Sir Nicholas in the audience as more and more of those around him stand up after being asked: 'Is there anyone in our audience tonight who owes their life to Nicholas Winton?' has been viewed millions of times online.

Addressing those gathered at the memorial service, Dame Esther again asked those who felt they owed their life to Sir Nicholas to stand up.

Moving: Nick Winton, the son of Sir Nicholas and Home Secretary Theresa May during the memorial service

Grateful: Evacuees rescued as children by the Kindertransport set up by Sir Nicholas pose at his memorial service. Sir Nicholas, who died last year, helped 669 Jewish children flee Nazi-occupied Czechoslovakia

Congregation: Hundreds turned out for the moving memorial service for Sir Nicholas Winton in central London

As dozens of people rose from their seats, she said: 'And it was at this stage that Nicky Winton himself turned round and saw for the first time the enormous impact his decision had made not only on one generation but on generations of Winton's children.

'Thank you very much. Nicky, I hope you're watching.'

Mrs May, who also addressed those gathered, said she felt privileged to have known Sir Nicholas, whose story she described as 'extraordinary'.

She recalled speaking to him at an event in 2010, shortly after the Conservatives formed a coalition government with the Liberal Democrats.

Amid laughter from the audience, she said: 'He said to me, 'I just want to tell you that coalition means compromise and that isn't always a bad thing. Never forget that'.'

The memorial service featured musical contributions including a children's choir who sang from Carl Davis's Last Train to Tomorrow which was written to tell the story of the Kindertransport children.

Sir Nicholas's son Nick said he hoped his father's example would continue to inspire others as they look to the future.

He said: 'It is his legacy to inspire and encourage all of us to be actively involved in our own communities. He's inspired me, my sister and many others I know, many of you in this room. And that is one of the ways his memory will live on and stay with us in the future.'

A memorial concert, in aid of today's child refugees and featuring actor Rupert Graves and cellist Alexander Baillie, will be held at St John's Smith Square on Friday.

Thankful: Lia Lesser, 85, who was rescued as a child by the Kindertransport set up by Sir Nicholas Winton, poses for a photo with her daughter Naomi at his memorial service today, which would have been his birthday

Saviour of a generation: Sir Nicholas met some of the children he helped save at the 70th anniversary of the Kindertransport trains in 2009

Royal meeting: After decades of relative anonymity, Sir Nicholas' achievements were made public in 1988. Pictured, meeting the Queen in 2012

Born in Hampstead, north London, in 1909, Nicholas Wertheim was the grandson of German Jewish immigrants who had moved to Britain in the 1860s.

His parents converted to Christianity and baptised their son. They would later choose to anglicise their surname, first to 'Wortham', and then to 'Winton' in 1938.

In 1923, Nicholas was sent to the newly-opened Stowe School, in Buckinghamshire. There, he proved himself to be a keen sportsman but lagged behind his peers in other subjects.

However any trouble he had at school did not dampen his ambition. Upon leaving, Nicholas decided to go into banking and soon sought out roles in institutions in both France and Germany, demonstrating a global mindset that was quite unusual among Englishmen of his generation.

Even at home in England, his life was markedly cosmopolitan. Nicholas would later recall how his parents would be visited by people from all over Europe, who kept the family abreast of what was happening in Germany.

'We'd had people who were being persecuted staying with us,' he said. 'We had families staying with us. We had refugees staying with us.'

Given this close personal connection, it is perhaps surprising that his journey to becoming the man hailed as the 'British Schindler' happened almost by accident.

In late 1938, then aged 28, Nicholas made plans to go on a skiing holiday with a friend, who was a teacher at Westminster School in London. But just weeks before they were due to fly, the friend said he would instead be travelling to Prague and asked if Nicholas would like to join.

Dogged determination: Sir Nicholas Winton with one of the children he rescued, and transported to Britain

Giving thanks: A woman who arrived in Britain on the Kindertransport kisses Sir Nicholas' hand in 2009

It was there that Nicholas discovered his friend was trying to help those who wanted to flee Czechoslovakia, whose northern and western regions were already partially occupied by Nazis. The events of Kristallnacht, at the time a recent memory, was a chilling demonstration of what Hitler and his followers were capable of. Many feared that Czechoslovakia was next and wanted to flee.

On their return to Britain, the friends worked together at the British Committee for Refugees from Czechoslovakia. While Nicholas felt the work was positive, it soon became clear that there was one vulnerable group of would-be refugees being overlooked: the young.

He later said: 'The commission was dealing with the elderly and people in the camps kept telling me that nobody was doing anything for the children.'

In show of bravery and initiative, Nicholas quickly returned to Prague and installed himself in a city centre hotel. With nothing more a dining room table and a pen, the young man set up a refugee organisation committed to saving Jewish children.

Over the next nine months, Nicholas worked every hour in both Prague and London to save as many children he could from the ominous shadow of Nazism.

He would later say that at the time his mission felt 'hopeless' as every family felt their children was most at risk.

Nicholas found a way to overcome British red tape, persuading the Home Office into giving entry permits to the eight train-loads of children who would arriving in the coming months.

He was also responsible for arranging foster care and raising money to cover the cost of the children's travel, as most of the desperate families were penniless.

Holocaust hero: Sir Nicholas was knighted in 2003 and was even nominated for the Nobel Peace Prize

British bureaucrats were not the only problem. Nicholas also had to convince Dutch officials to support his plan, as the trains had to cross through the Netherlands on their way to Britain.

Disturbingly, the first train load of children was actually rerouted to Germany, although he was eventually able to persuade the Dutch not to do so again.

On September 3, 1939, the ninth train-load of some 250 Jewish children sat at Prague station, bound for London. However, as that was the day that war was declared, the train was unable to depart. 'Within hours of the announcement, the train disappeared,' he later said.

'None of the 250 children on board was seen again. We had 250 families waiting at Liverpool Street that day in vain. If the train had been a day earlier, it would have come through. Not a single one of those children was heard of again, which is an awful feeling.'

Nevertheless, Nicholas had managed to save an astonishing 669 children, a brilliant feat.

Many in Nicholas' position might have returned to Britain trumpeting their successes, hailing themselves a hero. Instead, Nicholas slipped back into daily life, later working in an administrative capacity for the RAF.

After the war, he kept his extraordinary exploits relatively quiet, even from his beloved wife. Grete only discovered her husband's remarkable achievements when she found an old briefcase in the attic containing a scrapbook with lists of children and letters from their parents.

New lives: Some of the children saved by Sir Nicholas wave to the camera in this photo taken during the war

Life-changing moment: Sir Nicholas meets Vera Gissing, one of the children he saved, on That's Life in 1988

Forever grateful: Some of the descendants of the rescued children thanked Sir Nicholas for his work 

Explaining his reticence at sharing his story, Sir Nicholas — who was knighted by the Queen in 2003 — once said: 'There are all kinds of things you don't talk about, even with your family. Everything that happened before the war actually didn't feel important in the light of the war itself.'

In the Eighties, a Holocaust researcher called Dr Elizabeth Maxwell, who was married to tycoon Robert Maxwell, got in touch with the Wintons, asking for help.

Grete agreed to lend Dr Maxwell the scrapbook. From their, the incredible archive was passed on to That's Life, the popular Sunday programme hosted by Esther Rantzen.

Producers came up with the idea to introduce Nicholas to dozens of the children he had saved on television, in two consecutive shows.

The programmes were poignant and heartbreaking and, after it aired, Mr Winton's life changed forever. He would be celebrated wherever he went, became the subject of countless articles, and was catapulted to the status of national hero. International recognition soon followed.

In life, Sir Nicholas was typically modest about his achievements, however, saying that he received honours and accolades only because he had outlived all the others who had carried out so much humanitarian work.

'It turned out to be remarkable,' he reflected, 'but it didn't seem remarkable when I did it. Some people are born great, some achieve greatness, and some have greatness thrust upon them.' 

'IS THERE ANYBODY IN OUR AUDIENCE WHO OWES THEIR LIFE TO NICHOLAS WINTON?': POIGNANT MOMENT INCREDIBLE STORY WAS REVEALED ON TV

On February 27, 1988, Mr Winton's life changed forever. On that evening's edition of That's Life, the popular Sunday night show hosted by Esther Rantzen, his story was revealed.

The story was extraordinary, and revealed how nearly all the families of the rescued children had been slaughtered in the camps. And then, towards the end of the show, he was introduced to two women, Vera Gissing and Milena Grenfell-Baines, whose lives he had saved on his Kindertransport — children's transport.

Mrs Gissing later said of her saviour: 'He rescued the greater part of the Jewish children of my generation in Czechoslovakia. Very few of us met our parents again: they perished in concentration camps. Had we not been spirited away, we would have been murdered alongside them.' 

Man who saved her life: Nicholas with Vera Gissing, who was part of the Kindertransport, on That's Life

Nicholas was asked to return for the following week's show, this time accompanied by his beloved wife. 

It was this show that would be forever remembered by those who watched it. At one point, Esther Rantzen asked: 'Is there anybody in our audience tonight who owes their life to Nicholas Winton? If so, can you stand up please.'

There was a short, very British pause — and then some four rows of middle-aged people stood up. All of them owed their lives to that one man in the front row.

Nicholas stood up slowly, turned round, and couldn't quite believe how many there were. He acknowledged them with gentle nods, and then sat down to wipe away the tears that were welling up behind his thick-rimmed glasses.

However, those people in the audience represented just a tiny fraction of not only 669 lives he had saved, but also of their thousands of descendants who can thank Nicholas Winton for the fact that they were even born. And of course, as the years go by, that number will continue to swell.