But meantime the conquests of the Gur-Khan and his
defeat of Sanjar, just at a time which suits the story, are indubitable,
and this great advantage Oppert's thesis retains. As regards the claim to
the title of Presbyter nothing worth mentioning is alleged on either
side.
When the Mongol Conquests threw Asia open to Frank travellers in the
middle of the 13th century, their minds were full of Prester John; they
sought in vain for an adequate representative, but it was not in the
nature of things but they should find some representative. In fact they
found several. Apparently no real tradition existed among the Eastern
Christians of any such personage, but the persistent demand produced a
supply, and the honour of identification with Prester John, after hovering
over one head and another, settled finally upon that of the King of the
Keraits, whom we find to play the part in our text.
Thus in Plano Carpini's single mention of Prester John as the King of the
Christians of India the Greater, who defeats the Tartars by an elaborate
stratagem, Oppert recognizes Sultan Jalaluddin of Khwarizm and his
temporary success over the Mongols in Afghanistan. In the Armenian Prince
Sempad's account, on the other hand, this Christian King of India is
aided by the Tartars to defeat and harass the neighbouring Saracens, his
enemies, and becomes the Mongol's vassal.
