It is one of the few events to occur in southern Italy during the ninth century that is still commemorated today, largely through the walls named after Leo and for the Renaissance painting Battaglia di Ostia by Raphael.

A Christian armada, commanded by Caesar, son of Sergius I of Naples, was assembled off recently refortified Ostia, and Pope Leo IV came out to bless it and offer a mass to the troops.

Midway through the engagement, a storm divided the Muslims and the Christian ships managed to return to port.

[6] In the aftermath of the battle, much flotsam and jetsam washed ashore and was pillaged by the locals, per jus naufragii.

The prisoners taken in battle were forced to work in chain gangs building the Leonine Wall which was to encompass the Vatican Hill.