He distinguished himself in the fight against Turkish corsairs in the Aegean Sea, and received the title of "King and Despot of Asia Minor" from the titular Latin Emperor, Philip II.

In 1343 he was named commander of the Papal squadron in the Smyrniote crusade against Umur Bey, ruler of the Emirate of Aydin, and participated in the storming of Smyrna in October 1344.

His occupation was acknowledged by the impotent Byzantine emperor, Andronikos II Palaiologos, initially for a period of 10 years, but which was then renewed at five-year intervals.

[5][6] As lord of Chios, Martino and Benedetto fought with distinction against the Turkish pirates, who made their appearance in the Aegean in the early years of the 14th century.

[12] His constant efforts against the Turkish pirates earned him great praise by contemporary Latin writers, who wrote that if not for his vigilance, "neither man, nor woman, nor dog, nor cat, nor any live animal could have remained in any of the neighbouring islands".

In exchange, the Pope granted him the right to export mastic to Egypt—an exemption to the papal ban on trade with the Mamluks of Egypt—and proposed that the Zaccaria be given command of the Latin fleets in the Aegean.

Shortly after 1316, he bought the rights to the Barony of Chalandritsa from Aimon of Rans, although in a document of 1324 it appears that he possessed only half of it, the other being held by Peter dalle Carceri.

Martino haughtily rejected the demands and accelerated construction, but now his deposed brother Benedetto lodged a complaint with the emperor claiming the one-half share of the island's revenues that was his due.

With these events as an excuse, in autumn 1329 Andronikos III assembled a fleet of 105 vessels—including the forces of the Latin Duke of Naxos, Nicholas I Sanudo—and sailed to Chios.

Martino's wife and relatives were allowed to go free with their movable wealth, while most of the Zaccaria adherents chose to stay on the island as imperial officials.

Benedetto was offered the island's governorship, but he obstinately demanded to receive it as a personal possession in the same way as his brother had held it, a concession the emperor was unwilling to grant.

To celebrate this feat, Henry of Asti decided, against the advice of the other crusader leaders, to hold mass in the city's former cathedral, which lay in the no-man's-land between the citadel and the crusader-held lower town.