Nicholas of Cusa
Between 1440 and 1448 he spent much time in Germany. He worked with Cardinal Nicholas of Cusa, to placate the strong feelings of the German princes against Pope Eugene IV (1383 – 23 February 1447), to overcome their "neutrality" in the last and schismatic phase of the Council of Basel. The Council had taken the position that the ecumenical assembly of representatives of all the Church was superior to one member of the Church, even if he was Pope. In 1442 Carvajal was again sent along with Nicholas of Cusa by the Pope to the Diet at Frankfurt. Cardinal Giuliano Cesarini was sent to work on behalf of Pope Eugenius at the Council of Basel and to negotiate with Emperor Sigismund, and when the Council was dissolved, he was sent as Legate to Hungary (1442-1444). Cesarini was killed at the Battle of Varna.