This is a historical event that marks the passing of Pope Pius XII, the head of the Catholic Church from 1939 to 1958. His death on October 9, 1958, marked the end of a long and eventful papacy, during which he had to face the challenges of World War II
From Wikipedia
Pope Pius XII was head of the Catholic Church and sovereign of Vatican City from 2 March 1939 until his death on 9 October 1958.