[1] Simeon Rabban Ata was nominated as a sort of high-commissioner in charge of Christian affairs in Iran by Ogodei, and confirmed in this role by the Khan Guyuk.
[4] Simeon met Chormagan equipped with considerable powers so that freedom of faith could be respected in Iran, a policy which effectively protected Christianity in an Islamic land.
[8] He also had the role of an intermediary between Eastern and Western Christianity, and was able to write advice to the Pope: he even suggested him that he should make peace with Frederick II, Holy Roman Emperor.
[9] He was also an intermediary in the efforts at unifying the Eastern and Western churches: he transmitted to the Pope a profession of faith by the Jacobite patriarch Ignatius II in 1247, and gave to André de Longjumeau a letter in which the primacy of Rome was being recognized.
[10] Simeon met and had conversations with André de Longjumeau and Ascelin on the way to their missions to the Mongol realm in 1245, in the city of Tabriz.