Donato's first public charge was as ambassador to the court of
René II, Duke of Lorraine, in 1483. A string of ambassadorships followed: to the
Republic of Genoa in 1484; to the
Kingdom of Portugal in 1486; to
Maximilian I, elected
Holy Roman Emperor, in 1488; to the
Duchy of Milan in 1489–90; and to the
Holy See in 1491–92. In 1491,
Pope Innocent VIII nominated Donato's friend,
Ermolao Barbaro, to the office of
Patriarch of Aquileia. As it was illegal under Venetian law for ambassadors to accept gifts or positions of foreign heads of state, Donato was ordered to try to persuade Barbaro to renounce the appointment and return to Venice, but Barbaro did not. In 1492, Donato was elected
podestà and
captain of
Ravenna. In 1494–95, he served as one of the
avogadori di Comun (public prosecutors). Between 1495 and 1497, he was
podestà and vice-captain of
Brescia. There he hired the Albanian scholar
Marino Becichemo as a tutor for his son Filippo. While still
podestà of Brescia, he went on an embassy to the
Republic of Lucca in 1496. During 1497–1499, he reprised his role as ambassador to the Holy See. Afterwards he was
visdomino (Venetian representative) in the
Duchy of Ferrara, but there is some disagreement concerning the dates of his
visdominato: he appears to have been in Ferrara in July 1499, but other sources do not place him there until 1500 or even February 1501. From March to July 1501, he returned as ambassador to the Emperor-elect Maximilian. Donato was one of the
41 electors in the election of the
doge in 1501;
Leonardo Loredan was elected. He served as ambassador to the
Kingdom of France in 1501–02. In 1503–04, he was
podestà of
Cremona. In the latter year, he was elected to be one of the
Savi del Consiglio (wise men of the council). He was selected for the embassy of congratulation to newly elected
Pope Julius II that, for political reasons related to the downfall of
Cesare Borgia, did not set out until March 1505. Later that year he joined the
Ducal Council. In 1506, he was appointed
Duke of Crete. He wrote a letter describing the
Cretan earthquake of 1508. His office ended in 1508 and in 1509 he rejoined the Ducal council. In April 1509, Venice was placed under interdict by Julius II and targeted by the forces of the
League of Cambrai. Donato led the embassy that negotiated the lifting of the excommunication in February 1510. He continued on as ambassador to the Holy See, and, when the League fell apart, negotiated the creation of the
Holy League allying Venice with the Holy See,
Spain and
England on 5 October 1511. He was proclaimed a hero in Venice. Already ill at the time, he died in Rome two weeks later. The
Great Council awarded pensions to his widow and his nine surviving sons. According to Agostini, a Frenchman hearing of his death remarked, "He was a man of letters before he was a statesman; and he distinguished himself equally in both professions." ==Writings and reputation==