 Through Bar Sauma and other later envoys , such as <unk> de <unk> , Arghun promised the European leaders that if Jerusalem were conquered , he would have himself baptized and would return Jerusalem to the Christians . Bar Sauma was greeted warmly by the European monarchs , but Western Europe was no longer as interested in the Crusades , and the mission to form an alliance was ultimately fruitless . England did respond by sending a representative , Geoffrey of Langley , who had been a member of Edward I 's Crusade 20 years earlier , and was sent to the Mongol court as an ambassador in 1291 . 
