Sir Seretse Khama, the first President of Botswana and heir apparent to the kingship of the Bangwato people, brought independence and great prosperity to his nation after colonial rule. But for six long years from 1950, Seretse had been forced into exile in England, banned from his own country. His crime? To fall in love and marry a young, white English girl, Ruth Williams. Delving into newly released records, Susan Williams tells Seretse and Ruth's...