Marco Gradenigo was born in Venice in 14 October 1589 to the noble Gradenigo family,[2] son of Gian Giacomo. Member of a secondary branch of the Gradenigo family, his father managed to create an important position for himself in Venetian society as a lawyer, becoming wealthy and becoming the founder of the Di rio Marin branch of the family.[3]
In 1618 Marco Gradenigo was elected provveditore alle Pompe (a minor public office, aimed to limit the use of precious and luxury objects and their display). Other minors public offices were assigned to him up to 1624 when he became member of the Avogadoria de Comùn (similar to that of a modern State Attorney), and in 1626 he was appointed Superintendent of the Fortresses. In March 1627 the Maggior Consiglio finally appointed him as Duke of Crete (i.e. governor of Crete).[3]
Arrived in Candia in February 1628 Marco Gradenigo, with his resolute character, tackled head-on the main problem plaguing the city, i.e. the abuses of the local Venetian nobility against the Greek urban and rural population. He earned wide consensus with the public execution of the noble Zorzi da Ca' Fradello along with his armed men. In the capital Candia he supported the urban development, applied a tax exemption to foreigners intending to trade and ordered the first census of the population. However his health conditions forced him in autumn 1628 to delegate the govern to his great-captain Piero Giustinian.[3]