André de Longjumeau

André de Longjumeau (also known as Andrew of Longjumeau in English) was a 13th-century Dominican missionary and diplomat and one of the most active Occidental diplomats in the East in the 13th century. He led two embassies to the Mongols: the first carried letters from Pope Innocent IV and the second bore gifts and letters from Louis IX of France to Güyük Khan. Well acquainted with the Middle-East, he spoke Arabic and "Chaldean" (thought to be either Syriac or Persian).

Andrew's first mission to the East was when he was asked by the French king Louis IX to go and fetch the Crown of Thorns which had been sold to him by the Latin Emperor of Constantinople Baldwin II in 1238, who was anxious to obtain support for his tottering empire. Andrew was accompanied on this mission by brother Jacques.

Andrew of Longjumeau led one of four missions dispatched to the Mongols by Pope Innocent IV. He left Lyon in the spring of 1245 for the Levant. He visited Muslim principalities in Syria and representatives of the Nestorian and Jacobite churches in Persia, finally delivering the papal correspondence to a Mongol general near Tabriz. In Tabriz, André de Longjumeau met with a monk from the Far East, named Simeon Rabban Ata, who had been put in charge by the Khan of protecting the Christians in the Middle-East.

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