John Tsamblak
John Tsamblak or Zuan Tzamplakon was a member of the Tsamblak family, active as diplomat in the service of Moldavia, and as a mercenary leader. He is mentioned in connection with Stephen III's diplomatic missions to the Republic of Venice, and particularly the marriage arrangements with Maria of Mangup. He was nephew of Cyprian, Metropolitan of Kiev, and related to Gregory Tsamblak and, apparently, Cardinal Bessarion.