He had never forgotten the services of the legates Pandulf and Gualo to himself and his father, and was always ready to lend his aid to the political schemes of the popes, even when it was difficult to see that any English interests were involved in them.
The imperial legates and the captains of the Spanish guard in Siena crushed both government and people by continual extortions and by undue interference with the functions of the balia.
He fought with success against the German tribes, but soon left the defence of the Upper Rhine to his legates and returned to Rome, where he abandoned himself to all kinds of debauchery and excess.
Buda he endeavoured to make the worthy capital of a great realm, and the palace which he built there was pronounced by the papal legates to be superior to any in Italy.
It was during his pontificate that the 6th oecumenical council was held at Constantinople, to which he sent his legates and those from a Roman council held in 679.
The legates arrived on the 22nd of November, but no council assembled.
The custom prevailed of substituting legates a latere, simple priests or deacons of the Curia, for the regionary delegates, who had grown too independent; and that excellent instrument of rule, the Roman legate, carried the papal will into the remotest courts of Europe.
Datory expeditions of Bertrand du Poiet and Robert of Geneva were as ineffective as the descents of the emperors; and, though the cardinal Albornoz conquered Romagna and the March in 1364, the legates who resided in those districts were not long able to hold them against their despots.
He distinguished himself as one of Julius Caesar's legates in the Gallic campaigns, served in Britain, and afterwards under his brother in Cilicia.
In the latter case, the tribunal was to consist of bishops from the neighbouring provinces, assisted - if he so chose - by legates of the Roman bishop. The clauses thus made the bishop of Rome president of a revisionary court; and afterwards Zosimus unsuccessfully attempted to employ these canons of Sardica, as decisions of the council of Nice, against the Africans.