On 3 April 1438 Giacomo failed to be elected vice-captain in the Gulf, but on 11 July he was appointed superintendent of the thirty armed boats that were to operate on the Adige, while his father assumed command of the army on the Po.

[1] The following year, Loredan resumed service in the fleet; in May 1439 he brought Holy Roman Emperor Frederick III to Palestine and on 20 August he obtained command of the muda of Flanders; the long journey, which also touched Southampton, ended on 21 July 1440.

In October 1443, his son Luca was in Syria to trade, so it is probable that Giacomo was also involved in this activity; this would explain the absence of his name from politics until 23 June 1446, when he was elected Captain of the Gulf in place of Lorenzo Minio.

There was a question of keeping Ancona in alliance with Venice and supporting Francesco Sforza's reasons for Pesaro, while extorting the trade of Fano and Rimini, then under the dominion of Sigismondo Malatesta.

Then, on 1 October, he rejoined the Council of Ten and in this capacity on 31 May 1447 he was tasked with instructing the trial against Andrea Donà, son-in-law of the Doge, accused of treason, just as Jacopo Foscari had been two years earlier.

He accepted instead, on 6 January 1450, to go with Tommaso Duodo, both with the double title of ambassador and administrator, to the captain general of the Venetian army, Sigismondo Malatesta, where Andrea Dandolo already worked, with the task of supplying Brescia from the Veronese and completing the difficult negotiation with Francesco Sforza, who aimed to become Lord of Milan, as in fact would happen shortly thereafter.

In the frenetic evolution of events, the intrigues and ambitions of the leaders intertwined: this explains the reproach addressed by the Senate to Loredan and Duodo, on 29 January, for not having sufficiently worked with Bartolomeo Colleoni, despite the previous instructions to observe all possible savings.

On 7 February 1453 the Signoria therefore elected Girolamo Barbarigo as administrator in place of Loredan, who on 2 March was appointed Captain General of the Sea, the same position that his father had so often held with honour.

At this point, while the Senate was negotiating with Sultan Mehmed II, Loredan was ordered to proceed with the conquest of some islands and to damage the Ottoman settlements in the Dardanelles Straits.

The Venetian fleet was cruising the Aegean Sea for the whole of 1454, then took refuge in Modon, while Loredan repatriated to take his place among the Savi del Consiglio; the mandate should have covered the first half of 1455, instead it extended well beyond.

Appointed podestà in Padua in December 1460, Loredan stayed there until the spring of 1462; he was then Savio del Consiglio until August 1464; then, although 68 years old, he was nominated for the second time as Captain General of the Sea.

Elected on 7 April, he received commissions on 4 September, when he was already in the Levant; the war against the Turks, in the Morea, after a brilliant start was turning badly for the Venetians; Loredan's task was to raise the morale of the troops and at the same time weaken that of the adversaries, carrying out raids in the Straits, which he managed to block with his forty-two galleys.