Roncalli was elected pope on 28 October 1958 at age 76 after 11 ballots. His selection was unexpected, and Roncalli himself had come to Rome with a return train ticket to Venice. He was the first pope to take the pontifical name of "John" upon election in more than 500 years, and his choice settled the complicated question of official numbering attached to this papal name due to the antipope of this name. Pope John XXIII surprised those who expected him to be a caretaker pope by calling the historic Second Vatican Council (1962–65), the first session opening on 11 October 1962. His passionate views on equality were summed up in his famous statement, "We were all made in God's image, and thus, we are all Godly alike." John XXIII made many passionate speeches during his pontificate, one of which was on the day that he opened the Second Vatican Council in the middle of the night to the crowd gathered in St. Peter's Square: "Dear children, returning home, you will find children: give your children a hug and say: This is a hug from the Pope!"

Answer this question, if possible (if impossible, reply "unanswerable"): He was the first pope to take the pontifical name of "John" upon election in how long?
500 years