Arab raid against Rome

The Arab raid against Rome took place in 846. Saracen raiders plundered the outskirts of the city of Rome, sacking the basilicas of Old St Peter's and St Paul's-Outside-the-Walls, but were prevented from entering the city itself by the Aurelian Wall.

In the 820s, the Aghlabids of Ifriqiya (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.

A large force set sail from Miseno, which the Saracens had conquered in 845, and landed at Porto and Ostia in 846, annihilating the garrison of Nova Ostia. The Arabs struck following the Tiber and the Ostiense and Portuense roads, as the Roman militia hastily retreated to the safety of the Roman walls.

At the same time, other Arab forces landed at Centumcellae, marching towards Rome.

The Arab raiders seem to have known about Rome's extraordinary treasures. Some basilicas, such as St. Peter and Saint Paul Outside the Walls, 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". The most important among them were the golden cross erected above the alleged tomb of Petrus, the so-called Pharum Hadriani and the silver table donated to the church by Charlemagne, and adorned with a representation of Constantinople. As a result, the raiders pillaged the surroundings of the city and the two holy shrines. Contemporary historians believe the raiders had known exactly where to look for the most valuable treasures.

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Wikipedia