Pope John Paul I (1912 - 1978) reigned 26 August 1978 to his sudden death 33 days later. His reign is among the shortest in papal history. His sudden death has led to a number of conspiracy theories. His two immediate successors, John Paul II and Benedict XVI, later recalled the warm qualities of the late pontiff in several addresses.

In Italy, he is remembered with the appellatives of "Il Papa del Sorriso" (The Smiling Pope) and "Il Sorriso di Dio" (The smile of God). Time magazine and other publications referred to him as The September Pope. He is also known in Italy as "Papa Luciani".