(CNN) - Former Secretary of State Hillary Clinton, who first met Nelson Mandela in 1992, said Friday the anti-apartheid icon's death marks "the loss of a giant among us."
As a former first lady, U.S. senator and secretary of state, Clinton met with Mandela on a number of occasions over the past two decades.
"As I spent time with him starting in 1992 until just the last year and a half, I was always struck by the extraordinary depth of his self-knowledge, of his awareness about how hard it is to live a life of integrity and service," the potential 2016 presidential candidate said.
The last time she met with Mandela was in August 2012, when she visited him at his home in Qunu, South Africa, during her multi-nation trade and security tour through Africa.
Clinton was one of the few visitors who met with Mandela in his twilight years because of his failing health.
She also met with him 2009, her first year as the nation's chief diplomat, and in 2003, when she and her husband, former President Bill Clinton, visited him around his 85th birthday.
During President Clinton's second term, Mandela came to Washington at least three times–in 1998, 1999, and 2000.
On Friday, Hillary Clinton talked about going to Mandela's inauguration in 1994 after he was elected the first black president in South Africa. She said she was struck by how Mandela invited a few of his prison guards to the event, in addition to foreign dignitaries from around the world.
"He made the point of thanking his jailers and pointing out that of all the distinguished VIPs there, he was most grateful that these men - with whom he had exchanged words of recognition and acknowledgment of the others' humanity during the course of that long imprisonment - could be there as well," she said.
It was an example, she said, of how Mandela was someone who "demonstrated unequivocally how each of us can choose how we will respond to those injustices and grievances, those sorrows and tragedies that inflict all of human kind."