But we must inure ourselves, in the biography of Petrarch, to his over-estimation of favourites in the article of morals.
It was not long ere Petrarch was called upon to give a substantial proof of his regard for Azzo.

After the seizure of Parma by the confederate princes, Marsilio di Rossi, brother of Rolando, went to Paris to demand assistance from the French king.

The King of Bohemia had given over the government of Parma to him and his brothers, and the Rossi now saw it with grief assigned to his enemies, the Correggios.

Marsilio could obtain no succour from the French, who were now busy in preparing for war with the English; so he carried to the Pope at Avignon his complaints against the alleged injustice of the lords of Verona and the Correggios in breaking an express treaty which they had made with the house of Rossi.
Azzo had the threefold task of defending, before the Pope's tribunal, the lords of Verona, whose envoy he was; the rights of his family, which were attacked; and his own personal character, which was charged with some grave objections.

Revering the eloquence and influence of Petrarch, he importuned him to be his public defender.