While the Vatican has detailed laws and rituals to ensure the transfer of power when a pope dies or resigns, they do not apply if he is sick or even unconscious. And there are no specific norms outlining what happens to the leadership of the Catholic Church if a pope becomes totally incapacitated.

A scholar of global Catholicism writes how Francis has opened the church to the outside world in ways no pope had done before.

Discover the longest serving popes in history, whose enduring legacy continues to shape the Church long after their tenure has ended.