The South African anti-apartheid campaigner Winnie Madikizela-Mandela has died aged 81.
Her personal assistant confirmed her death this morning.
Her family said she died "peacefully" after being "in and out of hospital since the start of the year."
Mrs Madikizela-Mandela was married to the late Nelson Mandela for nearly four decades until 1996.
In a statement, her family said: "Mrs Madikizela-Mandela was one of the greatest icons of the struggle against Apartheid."
"She fought valiantly against the Apartheid state and sacrificed her life for the freedom of the country," reads the statement.
"Her activism and resistance to Apartheid landed her in jail on numerous occasions‚ eventually causing her banishment to the small town of Brandfort in the then Orange Free State.
"She kept the memory of her imprisoned husband Nelson Mandela alive during his years on Robben Island and helped give the Struggle for justice in South Africa one its most recognisable faces.
"She dedicated most of her adult life to the cause of the people and for this was known far and wide as the Mother Of The Nation."
They urged supporters to celebrate the gift of her life.
File photo of Winnie Madikizela-Mandela sitting beside Nelson Mandela and interim South African President Kalema Motlanthe in Johannesburg, South Africa, on April 19, 2009. Image: ABACA/ABACA/PA Images
Mrs Madikizela-Mandela held several Government positions throughout her political career and headed the African National Congress Women's League.
She was convicted in 1991 of killing an activist named Stompie Seipei who was found near her home with his throat cut.
She was sentenced to six years in prison, but it was reduced on appeal.
The couple separated in 1992, and he sacked her from his cabinet three years later after allegations of corruption.
She took her new surname, Madikizela-Mandela, after their divorce.