William II of Agen (also known as Guillaume d'Agen) was the Latin Patriarch of Jerusalem in 1261–70. Among other things, he was tasked by

Pope Urban IV Pope Urban IV ( la, Urbanus IV; c. 1195 – 2 October 1264), born Jacques Pantaléon, was the head of the Catholic Church and ruler of the Papal States from 29 August 1261 to his death. He was not a cardinal; only a few popes since his time hav ...

in 1263 by the papal bull '' Exultavit cor nostrum'' to investigate the legitimacy of an alleged ambassador with the Mongol Empire,

John the Hungarian ''Exultavit cor nostrum'' is a letter, also known as a Papal bull, from Pope Urban IV to the Mongol Ilkhanate leader Hulagu in 1263/1264. The letter was evidently in response to a message brought to Urban by John the Hungarian, who claimed to ...

References

* Peter Jackson, ''Mongols and the West'', p. 166 Latin Patriarchs of Jerusalem Year of birth missing Year of death missing 13th-century people of the Kingdom of Jerusalem {{RC-archbishop-stub