Conclave,” the film may have introduced movie-goers to the spectacular ritual and drama of a modern conclave, but the periodic voting to elect a new pope has been going on for centuries and created a whole genre of historical trivia.

As viewers of the film will know, the papal conclave will take place entirely behind the closed doors of the Sistine Chapel, beneath its world-famous Michelangelo frescoes. Nobody outside the confines of the Vatican will know the outcome until the plume of white smoke will curl from its chimney,