No Pope is obligated to change his name. This is a pious tradition (not Sacred Tradition). The practice arose when a pagan convert to Christianity became Pope and changed his name from Mercury (after the pagan Roman god) to John II in 533 C.E. Until then, the Popes kept their original names, from Peter (#1) to Boniface II (#55). Between John II (#56) and Sergius IV (#142) in 1009 C.E. only a few Popes changed their names. But since Sergius IV, it has been common practice for all Popes to change their name when elected pontiff except Adrian VI and Marcellus II. Pope Benedict XVI chose the name Benedict for several reasons. At his papal audience on April 27, 2005, he explained his motivations for adopting the name. "I want to call myself Benedict XVI to bind myself to the venerated Pope Benedict XV, who guided the church in a troubled period because of the First World War. He was a courageous and authentic prophet of peace and worked with valiant courage first to prevent the drama of war and then to limit its nefarious consequences. In his footsteps, I want to place my ministry at the service of reconciliation and harmony among individuals and peoples, deeply convinced that the great good of peace is, first of all, a gift of God, a fragile and precious gift to invoke, safeguard and build day after day with the help of everyone." Benedict XVI also said he chose the name to evoke the spirit of Saint Benedict, the founder of Western monasticism whose influence helped spread Christianity over Europe. "St. Benedict is very venerated in Germany, particularly in Bavaria, my homeland. He is a basic point of reference for the unity of Europe and a strong reminder of the undeniable Christian roots of its culture and civilization."
There have been 12 popes named Pius.
There have been 12 popes who have taken Pius as their name.
Both Leo and Innocent have been used by 13 popes.
There have been 23 popes named John, the most popular name by far.The most popular name historically chosen by the popes is John. No less than 23 popes have taken the papal office under this name.
Popes are chosen by cardinals in a conclave during which, as a group and as individuals, they pray for guidance of the Holy Spirit to help them choose the new pope.
There have been 266 popes so you need to be more specific.
Which of the 266 popes (2013) are you referring to? Please be specific.
Popes do not elect cardinals, they name them.
Popes are the head of the Catholic Church and chosen by the church. Kings are people who inherit the crown through family members.
There have been no popes named Jude.
There have been six popes named Adrian and six popes named Paul.
The majority of popes started as priests. However, it is not a requirement. Any male Catholic can be chosen. Pope Benedict XVI had virtually no experience as a diocesan priest as he spent most of his time in academics - teaching in universities - and was promoted directly from there to archbishop.