pope would recognize the treaty of Jaffa of 1229, which had ended the Sixth Crusade and restored Jerusalem to Christian rule. Ceremonies The public ceremony confirming the agreed "form of peace" was celebrated in San Germano on 23 July 1230. Frederick was present, while Gregory was personally represented by the friar Guala de Roniis. Church bells were rung. The assembly included princes and churchmen from Germany and Italy, several cardinals and imperial officials. The pope's charges against Frederick that led to his excommunication were publicly read by Patriarch Berthold of Aquileia, Archbishop Eberhard of Salzburg and Bishop Siegfried of Regensburg. Count Thomas of Acerra, on Frederick's behalf, swore on the Gospels to obey the church and the agreed "form of peace". Oaths were then sworn by Frederick's fidejussores, princes who pledged that for eight months from the day his excommunication was lifted they would assure his compliance and fight for the church if he reneged. All the oaths were recorded in "testimonial letters", to which the parties affixed their seals, including the imperial golden bull. The originals would go in the papal archives with copies be distributed to everyone else. After the ceremony, Guala returned to Rome. On 25 July, he was back in San Germano to lift the interdict that had been placed on it by Cardinal Pelagius of Albano during the war. On 28 July, Duke Leopold VI of Austria, who had played a leading role in negotiations, died suddenly. On 28 August at Ceprano, Thomas and John formally released Frederick II from his excommunication in a public ceremony. On 1 September, Gregory hosted Frederick in one of his family's houses in Anagni. The two shared the kiss of peace and held talks both in private and in public. The scene was staged as of a father (Gregory) receiving back a prodigal son (Frederick). Gregory on this occasion pardoned all the Sicilian bishops who had stayed loyal to Frederick. On 2 September, they supped together with Hermann von Salza. Their meeting is described both in Gregory's biography in the Liber censuum and in Frederick's letters. Independent accounts are in the Chronica regia Coloniensis and Breve chronicon de rebus Siculis. In September, Frederick issued an encyclical describing the ceremony of 28 August to all of Europe. Gregory sent out letters in the following months. These public ceremonies helped assure the public that peace had been reached. Enforcement The enforcement