Boris III of Bulgaria
Aware of Bulgaria's unreliability on the Jewish matter, the Nazis grew more suspicious about the quiet activities in aid of European Jewry of an old friend of Tsar Boris, Monsignor Angelo Roncalli (the future Pope John XXIII), the Papal Nuncio in Istanbul. Reporting on the humanitarian efforts of Roncalli, his secretary in Venice and in the Vatican, Monsignor Loris F. Capovilla writes: "Through his intervention, and with the help of Tsar Boris III of Bulgaria, thousands of Jews from Slovakia, who had first been sent to Hungary and then to Bulgaria, and who were in danger of being sent to Nazi concentration camps, obtained transit visas for Palestine signed by him."