Charles’s sack of Rome had made a Roman coronation impossible. Bologna, with its large Basilica San Petronio, was chosen as a suitable substitute location, but the change of venue presented significant problems from a symbolic point of view. The geography of the Eternal City and Saint Peter’s Basilica were vital to the centuries-old rituals of the event.
The imperial and papal courts therefore set about faithfully reproducing the symbolic geography of Rome in and around the Basilica of San Petronio. They also worked to ensure that the liturgy of the coronation Mass was performed as it would have been in Rome, drawing up a detailed ordo which specified the texts to be read and chanted in keeping with the age-old traditions.
Although Charles and Clement could not control the location of the ceremony, they were able to control the date: February 24, 1530, Charles’s thirtieth birthday. On the Church calendar, February 24 celebrates the life of Saint Mathias, the man chosen to replace Judas Iscariot as the twelfth apostle. By virtue of the fact that Charles was born on his feast day, Mathias was effectively Charles’s patron saint. The selection of this day drew attention to the relationship, symbolically casting Charles in Mathias’s place. The text of the proper for Mathias’s feast day consistently underscores the close connection between Christ, his apostles, and kingship, making it altogether appropriate for the occasion. The Gospel reading for the day, from the passage in Acts in which the selection of Mathias is described, followed immediately after the coronation itself.