E. Prester-John, Presbyter or Priest, or, as called by the Germans, Priester Johann, from which our English denomination, was prince of the Naymanni or Karaites, a tribe residing on tke river Kallassui or Karasibi, which, discharges itself into the Jenisei.

Heidenheimer rightly describes him: Als echter Kind seiner Zeit, war Peter Martyr Lehrer und Gelehrter, Soldat und Priester, Schriftsteller und Diplomat.