Papal Navy

The Papal Navy (Italian: Marina Pontificia, "Pontifical Navy") was the maritime force of the Papal States. Loosely construed, it was in sporadic existence from the Battle of Ostia (849) during the pontificate of Leo IV until the ascension of Pope Leo XIII in 1878.

Originally protected by the Byzantine navy, the Papal States found themselves in need of a naval force of their own following a Muslim raid on Rome in 843 and the sack of the city's basilicas extra muros in 846. Under the leadership of Caesar, prince of Naples, a force of Neapolitan, Amalfitan, Gaetan, and Papal ships repulsed the pirates off Ostia in 849.

Later, the Papal States subsidized various fleets during the Crusades and outfitted some squadrons of their own, which participated with Venice and others against the Ottoman Empire following the fall of Constantinople. With hired and affiliated ships from Tuscany and Malta, one Papal squadron participated in the Battle of Lepanto. Papal ships often assisted the Republic of Venice in her wars with the Ottoman Empire.

In 1715, Pope Clement XI constructed the Pontifical Arsenal near Porta Portese in Ripa Grande on the Tiber. In 1802, Napoleon donated two brigs to Pope Pius VII and the Papal Navy: the somewhat aged Saint Paul, and the brand-new Saint Pierre. Under the names San Paulo and San Petro they sat at Civitavecchia for some year until they were discarded.

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