Fond of religious meditations, in 1769 he asked and obtained permission to not hold an office because of ill health and bad hearing.

As the eldest son, he owned the Villa Manin di Passariano which was later inherited by his nephew, Lodovico Leonardo I (1771–1853).

Lodovico Leonardo was the son of his brother Giovanni (1736–1774) and Caterina (Pesaro), the heiress of a wealthy noble Israelite family who claimed to descend from Cyrus the Great.

Lodovico was elected Doge of Venice on 9 March 1789, the same year that would see the start of the French Revolution a few months later, on the first ballot (the electoral assembly was composed of 41 members).

His traditional coronation ceremony required him to throw coins to the Venetians, which cost more than 458,197 Lira, less than a quarter of which was paid from the funds of the Republic of Venice, the rest coming out of his own pocket.

When Napoleon invaded Italy, Venice, along with the Republic of Genoa, did not initially join the coalition of Italian states formed in 1795, instead maintaining neutrality.

A secret addition to the Treaty of Leoben, signed on 17 April 1797, gave Venice, alongside Istria and Dalmatia, to Austria.