The papacy is a jurisdictional office that grants the elected bishop the ability to govern the universal Church. As such, any male can technically be elected pope. It has sometimes happened that popes were elected before they even had proper orders, and so they had to receive these orders prior to their formally taking office. Over the centuries the Church has put in place ecclesiastical laws that prevent the above from happening, and that a pope be selected by ballot from among the college of cardinals, all of whom can cast one vote. Thus, these days, to become pope would involve being ordained a priest, then a bishop, then appointed a cardinal and perhaps, depending on your holiness, skills and politics, a pope.
Many people assume the pope is selected for his holiness. While this is indeed a desired quality, it is not true. The pope is selected for his administration skills above all, with holiness needed in order to keep him true. Holiness without skill is unable to lead, while these skills without holiness are liable to fall into error.
Odo was never the pope.
Saladin was never a pope.
Saladin was not a pope.
A priest could only become pope if he is elected by the cardinals in conclave.
You become a pope when you are elected as such in a secret conclave held in the Sistine Chapel of the Vatican to replace a pope who as either died or retired.
He was elected as pope on April 22, 1073.
There has never been a Pope John Benedict.
The pope has always been a Christian.
Vatican City
Pope John XXII became pope on August 7, 1316.
Since Pope Francis is the first and only pope by that name, there is no need for a number after his name. If a pope in the future also decides to take the name Francis, he will become Pope Francis II and then the original Pope Francis will become Pope Francis I.
He was 58 years old when elected as pope.