Since the position of Pope is required to be "usque ad mortem" (until
death), when the Pope of
Rome resigns, quits, or is removed from his Pontificate before his natural
death, such leaving of office is known as Pontificatus Interruptus.
Due to his resignation from office, Pope Benedict XVI, whose previous
name was title and
name was Cardinal Ratzinger,
will forever be known as Pontificatus Interruptus.