Morgan Freeman looks like Nelson Mandela. Morgan Freeman sounds like Nelson Mandela. Morgan Freeman specializes in playing quietly-dignified men of gently-divine inspiration... like Nelson Mandela. Back when I was a Blockbuster clerk, I remember on two seperate occasions meeting two entirely-unrelated folks who were CONVINCED that Morgan Freeman's best role was having played Nelson Mandela... though he never had. "Everybody knows" Morgan Freeman ought to play Nelson Mandela.
So, in a new movie, Morgan Freeman will play Nelson Mandela.
So, that happened.