Arab raid against Rome

In 846, Arab raiders plundered the outskirts of Rome, sacking Old St. Peter's and St. Paul's-Outside-the-Walls, but were prevented from entering the city itself by the Aurelian Wall.

Background
In the 820s, Arabs (known by medieval Italians as the Saracens) began the conquest of Sicily. In 842, Arab forces tried to capture Ponza, but were beaten off by a combined fleet from Naples and Gaeta. However, the same year they took Messina, Sicily. Around the same time Radelchis I of Benevento and Siconulf of Salerno, rivals engaged in civil war, hired Arab mercenaries to fight in Campania.

Raid
A large force set sail from Campania, landed at Porto and Ostia in 846. The Arabs struck as the Roman militia hastily retreated to the safety of the Roman walls.

The Arab raiders seem to have known about Rome's extraordinary treasures. Some holy - and impressive - basilicas, such as St. Peter's Basilica, were outside the Aurelian walls, and thus easy targets. They were "filled to overflowing with rich liturgical vessels and with jeweled reliquaries housing all of the relics recently amassed". As a result the raiders pillaged the holy shrines, including St. Peter's basilica. Contemporary historians believe the raiders had known exactly where to look for the most valuable treasures.

Aftermath
Shortly after the siege Pope Leo IV built a strong wall on the right bank of the Tiber, in order to protect the Church of St. Peter. The encircled territory, defended by Castel Sant'Angelo, was named after the pope Leonine City, and was considered a separate town, with own administration. It joined the city in the sixteenth century, becoming the fourteenth rione of Rome, Borgo. In 849, another Arab raid against Rome's port, Ostia, would be repelled; the city was never again attacked by an Arab fleet.

Saracinesco, located about 40 kilometres (25 mi) northeast of Rome, was founded by Arabs from the 846 raid against Rome.