Thousands of mourners braved South Africa's summer rain as they packed the Soccer City stadium in Johannesburg for a national memorial for Nelson Mandela.

Despite pouring rains, the atmosphere inside the stadium was celebratory, with people in colorful wear dancing, blowing "vuvuzelas" - plastic horns - and singing songs from the country's anti-apartheid struggle.

The memorial event will pay tribute to a life of imprisonment and political struggle that ended in triumph and consecrated Mandela as a global symbol of integrity and forgiveness.

The fact that the visiting leaders - more than 90 are expected - include some from nations still locked in antagonism, such as Cuba and the United States, adds resonance to the homage being held at the gigantic bowl-shaped stadium, the venue of the 2010 World Cup final.