This I hadn't heard before: Mandela had a JW connection (link to Freeminds). Mandela's wife was a Witness.
They went on to have four children together one of which died after nine months. Somewhere in the early 1950’s Evelyn converted to becoming a Jehovah’s Witness. This conversion spelled the end of their marriage. Why? Jehovah’s Witnesses teach that the end of the world is coming and all that are not Jehovah’s Witnesses will be destroyed by God. This is a core teaching they have preached for 150 years. In interviews Mrs. Mandela stated:
“Ms. Mandela, a member of the Jehovah’s Witness denomination, separated from Mr. Mandela in 1955 after what her husband described in his autobiography, 'Long Walk to Freedom,' as an irreconcilable conflict between politics and religion."
In another,
"There was a strong lobby within the African National Congress circles for Mr. Mandela to remarry her, but Sister Evelyn stood her ground that she did not consider remarriage and above all her former husband is not a worshiper of Jehovah like herself."