Every pope is by definition a remarkable man. But the popes whose stories you'll read here were chosen because they reveal how the papacy developed. They show us how Christ kept his promise to his bride, the Church, not only in her health but also in her sickness. The great popes advanced our understanding of Christian doctrine. But even more remarkable, the worst popes could do nothing to damage the teaching of the Church.

That's why, even in its darkest moments, the story of the papacy is a story of triumph. And that's why it's worth knowing these twelve popes.