It quickly became clear the largest array of prime ministers and presidents the world has ever seen will converge on South Africa next week for memorial events and the state funeral.
It is expected that among those attending will be US President Barack Obama and Prime Minister David Cameron.
In many countries, people, inspired by Mandela's struggle for a democratic South Africa, staged quiet vigils, creating impromptu shrines with flowers and messages next to statues honouring the international statesman, who died on Thursday night aged 95.
Beneath the one in London's Parliament Square, flowers and pictures were laid. A tribute on one card simply read: "Thank you for the sacrifices you made for all of us."
The grief felt in the UK mirrored that felt around the world as evidenced by social media website Twitter. In the five hours after the news of Mandela's death broke, more than seven million tweets were posted, with a peak of 95,000 per minute.
Flags were put at half-mast on government buildings across numerous cities from Washington to London and Paris to Sydney. The European Union, the International Olympic Committee and Fifa, the world football body, also ordered their flags to be lowered.
This weekend, a minute's applause will take place at football matches in the Scottish Professional Football League, the English Premier League, Football League and FA Cup while Fifa said there would be a minute's silence ahead of the next round of international football matches.
Westminster Abbey will hold a national service of thanksgiving for the life of Mandela after his state funeral on December 15. A book of condolence has been opened in St Margaret's Church at the abbey.
Outside South Africa House in London's Trafalgar Square, there was a growing celebratory atmosphere. A strong smell of incense filled the air as crowds remembered Mandela with a constant flow of song and dance. As the day wore on hundreds formed a queue to sign a book of condolence there. The first to pen a message was Mr Cameron.
He wrote: "Your cause of fighting for freedom and against discrimination, your struggle for justice, your triumph against adversity - these things will inspire generations to come. And through all of this, your generosity, compassion and profound sense of forgiveness have given us all lessons to learn and live by."
Ed Miliband, the Labour leader, who also signed the book of condolence, called Mandela's work to unite South Africa in the face of personal hardship and oppression "extraordinary". He said: "The world has lost the inspirational figure of our age. Nelson Mandela taught people across the globe the true meaning of courage, strength, hope and reconciliation."
At Westminster, John Bercow, the Commons Speaker, announced that on Monday normal parliamentary business would be postponed to enable MPs the chance to pay their own tributes to Mandela.
They will be led by Mr Cameron and Mr Miliband. Mr Bercow suggested the whole day's business would be cancelled, making clear MPs' "principal occupation" would be honouring the late president.
The Speaker described him as an "icon", saying Mandela's strength of character in forgiving the regime that had imprisoned him for over a quarter of a century was "beyond the realm of normal imagination".
A separate book of condolence will be opened in the Commons library for MPs, peers and staff to sign. Also next week, a photo of the anti-apartheid campaigner will be placed in Portcullis House, Westminster's modern annexe, where many MPs have their offices.
Yesterday, the Queen saw a plaque commemorating Mandela's 1996 visit to the UK Parliament after saying she was "deeply saddened" to learn of his death. She was shown it by Mr Bercow as she visited Westminster Hall to view the Diamond Jubilee window gifted to her by MPs and Lords.
Earlier, she paid tribute to the late president, saying he had "worked tirelessly for the good of his country".
Other tributes from senior figures in various fields continued to pour in.
Jesse Jackson, the American civil rights leader, said: "The imprint he left on our world is everlasting."
Baroness Lawrence, the mother of murdered black teenager Stephen Lawrence, credited him with starting the campaign for justice for her son's killers.
The Prince of Wales described the Nobel Peace Prize winner as "the embodiment of courage and reconciliation".
Pope Francis said Mandela had forged "a new South Africa built on the firm foundations of non-violence, reconciliation and truth".
An old ally in the fight against apartheid, Kenneth Kaunda, the former Zambian President, hailed his friend as "a great freedom fighter".
Bashar al Assad, the Syrian President, called the South African statesman "an inspiration in the values of love and human brotherhood".
Ban Ki-moon,the UN secretary general, said he was "a giant for justice" whose "selfless struggle for human dignity, equality and freedom" inspired many people around the world.
"No-one did more in our time to advance the values and aspirations of the United Nations," he said.
Malala Yousafzai, the Pakistani teenage activist, who survived a Taliban assassination attempt, said: "He belongs to the whole world because he is an icon of equality, freedom and love, the values we need all the time everywhere."
There were also many tributes from the world of sport.
Boxing great Muhammad Ali said: "He made us realise we are our brother's keeper and that our brothers come in all colours.
A clearly emotional Ernie Els, the South African golfer, said: "It is a very sad day. We have lost one of the iconic leaders of our time."
Meantime, from the world of music Sir Bob Geldof said: "History stops, kneels and bows its head. His like is rare in all of human history."
Fellow Irishman Bono, the U2 frontman, added: "It was as if he was born to teach the age a lesson in humility, in humour and above all else in patience."