"He no longer belongs to us. He belongs to the ages," said President Barack Obama as he bid farewell to the beloved former South African President, Nelson Mandela from the White House.

"Nelson Mandela taught us so much about so many things," said former President Bill Clinton, whose term overlapped with Mandela's. "Perhaps the greatest lesson, especially for young people, is that, while bad things do happen to good people, we still have the freedom and responsibility to decide how to respond to injustice, cruelty and violence and how they will affect our spirits, hearts and minds," PBS reports.

Nelson Mandela, who died at 95, led an extraordinary life, "he became one of the world's most beloved statesmen and a colossus of the 20th century when he emerged from 27 years in prison to negotiate an end to white minority rule in South Africa."

South African President Jacob Zuma made the announcement at a news conference late Thursday, saying "we've lost our greatest son."

"His death closed the final chapter in South Africa's struggle to cast off apartheid, leaving the world with indelible memories of a man of astonishing grace and good humor," The Associated Press reported. "Rock concerts celebrated his birthday. Hollywood stars glorified him on screen. And his regal bearing, graying hair and raspy voice made him instantly recognizable across the globe."

Back in 2008, I spoke with Grammy award-winning singer Josh Groban about his involvement in honoring Mandela for his 90th birthday celebration. Groban, who sold out arenas all around the world, told me that he was most moved when he was asked to sing at Mandela's birthday celebration; it was one of the highlights of his very successful career.

"Meeting him was one of the greatest honors of my life," Groban said. "I mean I don't get star-struck, but being in the presence of such a great human being was very humbling," Groban told me of his first encounter with the Nobel Peace Prize-winning former South African president.

"I am so thrilled that I am going to London to perform for his 90th birthday," he said.

The Nelson Mandela 90th Birthday Concert was hosted by Will Smith and took place on Friday, June 27, 2008 in London's Hyde Park.

The memorable event featured legendary folk-rock singer Joan Baez and Jerry Dammers (an Artists Against Apartheid organizer) whose song "Free Nelson Mandela" ignited the 80's anti-apartheid movement in the U.K., the late Amy Winehouse, Leona Lewis, U2, Queen + Paul Rodgers, Annie Lennox, Simple Minds, Sir Paul McCartney, The Spice Girls, Sugababes, Dame Shirley Bassey, Keane and Razorlight.

The impressive lineup also included an array of Africa's most praised artists, including Johnny Clegg, Soweto Gospel Choir and Papa Wemba. Other prominent figures in attendance were British Prime Minister Gordon Brown, former U.S. President Bill Clinton and U.S. talk show host Oprah Winfrey.

The concert marked the 20 years since London publicly urged Mandela's release from jail with Mandela's 70th Birthday Concert in 1988.

Groban first met Mandela when he was performing at a concert in Johannesburg, South Africa. He was instantly impressed with not only the sheer presence of Mandela, but his selflessly dedicating his entire life to helping his people.

Mandela appointed Groban an official ambassador for Mandela's Project 46664, a campaign to help raise global awareness of HIV/AIDS in Africa. Project 46664 is a reference to Mandela's prison number when he was jailed by South Africa's apartheid authorities.

"I was very honored to be invited to meet him. I was in Johannesburg for a concert," Groban said. "I told him (Mandela) that I would be at his beck and call for anything he needed, as far as spreading the word for his amazing organization. So, I have been proud to be his ambassador for his 46664 foundation. We have done a lot of work and raised a lot of money for his foundation and my foundation."

Inspired by Mandela's resonating desire to help others, Groban established the Josh Groban Foundation in 2004 that helps children in need throughout the world with education, healthcare, and the arts.