Conclave notes - part 4

Images of past Popes at St Paul's basilica, Rome.

Choosing a papal name is not a required Catholic practice, but over the centuries, it has become a tradition. The first pope to change his name was John II in 533. His birth name was Mercurius or Mercury, the name of a pagan god. Once an exception, the practice became tradition in 996, when Bruno, the first German pope, became Gregory V. The last pope to keep his birth name was Marcellus II in 1555.
Among the names that the new Pontiff may choose are these, with the respective Roman numeral or number after each name. He may be one of these, besides others who were chosen in the early centuries: 
John Paul III, Benedict XVII, Paul VII, John XXIV, Pius XIII, Gregory XVII, Innocent XIV, Julius IV, Leo XIV, Clement XV, Alexander IX, Sixtus VI, Urban IX, Marcellus III, Adrian VII, Callixtus IV, Nicholas VI, Eugene V, Martin VI, Boniface X, Celestine VI, Honorius V, Lucius IV, Anastasius V, Gelasius III, Paschal III, Victor IV, Stephen X, Damasus III, Sylvester IV, Sergius V, Agapetus III, Marinus III, Felix V, Theodore III, Romanus II, Formosus II, Valentine II, Zachary II, Constantine II, Sisinnius II, Severinus II, Agatho II, Adeodatus II and Vitalian II.

Cardinal Prospero Grech, OSA

After the Cardinals enter the Sistine chapel, they will hear a sermon of exhortation from an illustrious preacher, and tomorrow the preacher chosen is the Maltese Cardinal Prospero Grech. He hails from Vittoriosa, and was born on December 24, 1925. He joined the Augustinian Order in 1943 and three years later was sent to Rome to further his theological studies. He was ordained priest on March 25, 1950. Cardinal Grech has been working with Pope Benedict XVI for 20 years. Their working relationship started when Cardinal Joseph Ratzinger was Prefect of the Congregation for the Doctrine of the Faith. It continued to develop when Grech was nominated member of the Pontifical Theological Academy. Cardinal Grech’s election to the College of Cardinals on February 18, 2012, is first and foremost, a personal honor. It signified the great esteem in which he is held by the Holy See. His nomination as a Cardinal was in recognition of the bountiful contribution that the Church in Malta has made and continues to make to the universal Church. And his being chosen to preach at such a momentous moment is a further affirmation of this.