“I have taken a moment here to rest, to steal a view of the glorious vista that surrounds me, to look back on the distance I have come. But I can rest only for a moment, for with freedom come responsibilities, and I dare not linger, for my long walk is not yet ended.”

So ends Nelson’s Mandela’s Long Walk to Freedom, one of the best selling political memoirs of all time. But after 115 chapters and 751 pages, charting his rise from herd boy to prisoner to president, the narrative slides to halt in 1994. Which begs the question: what really happened next?

More than 20 years later, the world will finally get an answer with the posthumous publication of a sequel based on a little known manuscript that Mandela wrote by hand but never completed, chronicling his time as South Africa’s first black president. Pan Macmillan announced on Tuesday that it has acquired the UK and Commonwealth rights to the book which, as yet untitled, will hit shelves next year.