The Church has been through many moments of seismic change, sometimes (but not always) championed by a visionary pope. The last great upheaval took place half a century ago, when the Vatican abandoned the Latin mass and radically reconceived the function of the liturgy. Now Pope Francis has inspired some and infuriated others with his promise of change. The first Jesuit pope and the first from the Americas, he has tackled social inequality, sexuality, and the environment, but can he really bring about change? And, equally important, should he? Pulitzer Prize-winning historian Garry Wills offers a thrilling examination of five pivotal moments in the history of the Catholic Church to illuminate our understanding of the new pope and the institutional challenges he faces. By turning to the past he reveals how, over the centuries, the Church has reinvented itself most effectively when it has learned to acknowledge and confront its mistakes.