In 1438 Bessarion (1403 - 1472) was sent by the Emperor John VIII Palaeologos to the Council of Ferrara/Florence to plead for western support in Constantinople's final struggle against the Ottoman Turks.
Despite the failure of the council to dispatch aid to Byzantine Empire, Pope Eugenius IV recognised Bessarion's constructive role in the deliberations by making him a cardinal. Bessarion remained in Italy and in 1463 was made Patriarch of Constantinople, by then in Turkish hands, by Pope Pius II.
In July 1463, Pius II sent Bessarion to Venice as legate a latere. In order to win the favour of a city notorious for its reluctance to allow credit to any 'foreign' notable, Bessarion donated his celebrated library of Greek manuscripts to the city, where they became the nucleus of the Biblioteca Marciana. He also took a particular interest in the scuole, in particular the prestigious Scuola di S. Maria dei Battuti della Carita, which enjoyed the patronage of the influential Guardian Grande, Ulisse Aliotti. In August, in the presence of Aliotti, prominent bishops and other assembled grandees, Bessarion presented the Reliquary of the True Cross to the Scuola, reserving its use for his lifetime.
In May 1472, when leaving Rome for France, the Cardinal transferred the precious object to Venice. A letter of 6 July 1472 records the festa on the arrival of the reliquary and the procession marking its translation from San Marco to the Scuola, where it was installed on the altar already prepared for it in the Sala dell' Albergo. Bessarion himself died at Ravenna on 19 November of the same year.
Gentile Bellini's painting Cardinal Bessarion attended by the two brothers of the Scuola della Carita in prayer with the Bessarion reliquary (National Gallery, London) was commissioned by the Guardian Grande, Ulisse Aliotti, in 1472-3 to form the door of the tabernacle that housed the reliquary in the Sala dell' Albergo. The reliquary is still in the Carita, now the Gallerie dell'Accademia, in Venice.