Duke Hildeprand of Spoleto to procure divine favour or vouchsafe his land to God by donating it to the abbey. The charters of three grants the duke made to Farfa credit the monks with suggesting them, a sign of Probatus' gift for diplomacy. In 773, before April, Desiderius was pressuring Rome with his army when Pope Hadrian I sent a delegation led by Probatus and twenty of his senior monks to deal with the king. The purpose of this expedition was to procure the return of some cities which had been captured from the Duchy of Rome (which lay outside Desiderius' kingdom); it was the purpose of another papal delegation later that year to receive the cities, which, however, Desiderius did not agree to return. Probatus' embassy can be viewed as an effort, ultimately unsuccessful, to preserve the political order and its peace ("to save Desiderius from himself [since] many in the duchy [of Spoleto] did not share the Lombard king's confidence in his own military strength"). In 774 Italy fell to Charlemagne, king of the Franks, after a successful siege of the capital, Pavia, and Desiderius was taken into captivity. Securing immunity and independence (775–78) Probatus was the first Italian abbot to get confirmation of his abbey's holdings and of its spiritual immunity (from secular and prelatical authority) from the Frankish king. In order to obtain these privileges it was necessary for Probatus to travel to the Frankish court at Quierzy in 775. There, in his royal villa, Charlemagne issued his first privilege for Farfa on 22 May, exempting it from episcopal jurisdiction and confirming its freedom of abbatial election. A second privilege was issued on 29 May granting it spiritual immunities. Probatus returned to Farfa in January 776 and a flood of donations to the abbey, now patronised by the most powerful ruler in western Europe, followed. The years 776–78 were the most fruitful in the early development of Farfa's territory. In those years Farfa received seven grants from Duke Hildeprand, who had been confirmed in his position by Charlemagne. The confirmation of spiritual immunity was important at the time, since Farfa was dealing with its first recorded jurisdictional dispute with the Papacy. According to the Libellus constructionis Farfensis, Pope Hadrian had ordered that disputes between Farfa and some men from Rome be settled by his prior vestiarius, Miccio. This was a secular official pertaining to the secular