The eighteen cardinals who met to elect a successor to Clement IV.
At Avignon, where he appeared in August 1352, Rienzi was tried by three cardinals, and was sentenced to death, but this judgment was not carried out, and he remained in prison in spite of appeals from Petrarch for his release.
Received the cardinal archbishop of Bordeaux and determined to support the cardinals at Pisa against both popes.
With unbending dignity, however, he retained his antagonism; and shortly afterwards he was one of the thirteen cardinals who refused to attend the ceremony of the emperor's marriage with Marie Louise.
On the 3rd of July 1517 he published the names of thirty-one new cardinals, a number almost unprecedented in the history of the papacy.