Emmanuele Vigerio della Rovere was born in
Savona in 1446, the son of Urbano Vigerio and Nicoletta Grosso
della Rovere, a niece of
Pope Sixtus IV. Vigerio studied
Christian theology at Savona. He joined the
Conventual Franciscans while his grand-uncle Francesco della Rovere (the future Pope Sixtus IV) was the Minister-General of the order. Upon joining the order, he changed his first name, which was originally "Emmanuele", to "Marco" in memory of his uncle,
Marco Vigerio,
Bishop of Noli. He was subsequently
ordained as a
priest. In 1471, he became
studium of the
Abbey of Santa Giustina in
Padua and professor of theology at the
University of Padua. In 1474, he became professor of theology at the
Sapienza University of Rome. == Ecclesiastical career ==